delivered the opinion of the Court.
I.
This suit was instituted by appellee, who is qualified to vote in primary and general elections in Fulton County, Georgia, to restrain appellants from using Georgia’s county unit system as a basis for counting votes in a Democratic primary for the nomination of a United States Senator and statewide officers, and for declaratory relief. Appellants are the Chairman and Secretary of the Georgia State Democratic Executive Committee, and the Secretary of State of Georgia. Appellee alleges that the use of the county unit system in counting, tabulating, consolidating, and certifying votes cast in primary elections for statewide offices violates the Equal Protection Clause and the Due Process Clause of the Fourteenth Amendment and the Seventeenth Amendment. As the constitutionality of a state statute was involved and the question was a substantial one, a three-judge court was properly convened. See 28 U. S. C. § 2281; United States v. Georgia Public Service Comm’n, 371 U. S. 285.
Appellants moved to dismiss; and they also filed an answer denying that the county unit system was uncon-constitutional and alleging that it was designed “to achieve a reasonable balance as between urban and rural electoral power.”
Under Georgia law each county is given a specified number of representatives in the lower House of the Gen*371eral Assembly.1 This county unit system at the time this suit was filed was employed as follows in statewide primaries: 2 (1) Candidates for nominations who received the highest number of popular votes in a county were considered to have carried the county and to be entitled to two votes for each representative to which the county is entitled in the lower House of the General Assembly; (2) the majority of the county unit vote nominated a United States Senator and Governor; the plurality of the county unit vote nominated the others.
Appellee asserted that the total population of Georgia in 1960 was 3,943,116; that the population of Fulton County, where he resides, was 556,326; that the residents of Fulton County comprised 14.11% of Georgia’s total population; but that, under the county unit system, the six unit votes of Fulton County constituted 1.46% of the total of 410 unit votes, or one-tenth of Fulton County’s percentage of statewide population. The complaint further alleged that Echols County, the least populous county in Georgia, had a population in 1960 of 1,876, or .05% of the State’s population, but the unit vote of Echols County was .48% of the total unit vote of all counties in Georgia, or 10 times Echols County’s statewide percentage of population. One unit vote in Echols County represented 938 residents, whereas one unit vote in Fulton County represented 92,721 residents. Thus, one resident in Echols County had an influence in the nomination of candidates equivalent to 99 residents of Fulton County.
*372On the same day as the hearing in the District Court, Georgia amended the statutes challenged in the complaint. This amendment3 modified the county unit system by allocating units to counties in accordance with a “bracket system” instead of doubling the number of representatives of each county in the lower House of the Georgia Assembly. Counties with from 0 to 15,000 people were allotted two units; an additional one unit was allotted for the next 5,000 persons; an additional unit for the next 10,000 persons; another unit for each of the next two brackets of 15,000 persons; and, thereafter, two more units for each increase of 30,000 persons. Under the amended Act, all candidates for statewide office (not merely for Senator and Governor as under the earlier Act) are required to receive a majority of the county unit votes to be entitled to nomination in the first primary. In addition, in order to be nominated in the first primary, a candidate has to receive a majority of the popular votes unless there are only two candidates for the nomination and each receives an equal number of unit votes, in which event the candidate with the popular majority wins. If no candidate receives both a majority of the unit votes and a majority of the popular votes, a second run-off primary is required between the candidate receiving the highest number of unit votes and the candidate receiving the highest number of popular votes. In the second primary, the candidate receiving the highest number of unit votes is to prevail. But again, if there is a tie in unit votes, the candidate with the popular majority wins.
Appellee was allowed to amend his complaint so as to challenge the amended Act. The District Court held that the amended Act had some of the vices of the prior Act. It stated that under the amended Act “the vote of *373each citizen counts for less and less as the population of the county of his residence increases.” 203 F. Supp. 158, 170, n. 10. It went on to say:
“There are 97 two-unit counties, totalling 194 unit votes, and 22 counties totalling 66 unit votes, altogether 260 unit votes, within 14 of a majority; but no county in the above has as much as 20,000 population. The remaining 40 counties range in population from 20,481 to 556,326, but they control altogether only 287 county unit votes. Combination of the units from the counties having the smallest population gives counties having population of one-third of the total in the state a clear majority of county units.” Ibid.
The District Court held that as a result of Baker v. Carr, 369 U. S. 186, it had jurisdiction, that a justiciable case was stated, that appellee had standing, and that the Democratic primary in Georgia is “state” action within the meaning of the Fourteenth Amendment. It held that the county unit system as applied violates the Equal Protection Clause, and it issued an injunction,4 not against conducting any party primary election under the county unit system, but against conducting such an election under a county unit system that does not meet the requirements specified by the court.5 203 F. Supp. *374158. In other words, the District Court did not proceed on the basis that in a statewide election every qualified person was entitled to one vote and that all weighted voting was outlawed. Rather, it allowed a county unit system to be used in weighting the votes if the system showed no greater disparity against a county than exists against any State in the conduct of national elections.6 Thereafter the Democratic Committee voted to hold the 1962 primary election for the statewide offices mentioned on a popular vote basis. We noted probable jurisdiction. 370 U. S. 921.
II.
We agree with the District Court that the action of this party in the conduct of its primary constitutes state action within the meaning of the Fourteenth Amendment. Judge Sibley, writing for the court in Chapman v. King, 154 F. 2d 460, showed with meticulous detail the manner in which Georgia regulates the conduct of party primaries (id., pp. 463-464) and he concluded:
“We think these provisions show that the State, through the managers it requires, collaborates in the conduct of the primary, and puts its power behind the rules of the party. It adopts the primary as a part of the public election machinery. The exclusions of voters made by the party by the primary rules become exclusions enforced by the State.” Id., p. 464.
We agree with that result and conclude that state regulation of this preliminary phase of the election process *375makes it state action. See United States v. Classic, 313 U. S. 299; Smith v. Allwright, 321 U. S. 649.
We also agree that appellee, like any person whose right to vote is impaired (Smith v. Allwright, supra; Baker v. Carr, supra, pp. 204-208), has standing to sue.7
Moreover, we think the case is not moot by reason of the fact that the Democratic Committee voted to hold *376the 1962 primary on a popular vote basis. But for the injunction issued below, the 1962 Act remains in force; and if the complaint were dismissed it would govern future elections. In addition, the voluntary abandonment of a practice does not relieve a court of adjudicating its legality, particularly where the practice is deeply rooted and long standing. For if the case were dismissed as moot appellants would be “free to return to . . . [their] old ways.” United States v. W. T. Grant Co., 345 U. S. 629, 632.
III.
On the merits we take a different view of the nature of the problem than did the District Court.
This case, unlike Baker v. Carr, supra, does not involve a question of the degree to which the Equal Protection Clause of the Fourteenth Amendment limits the authority of a State Legislature in designing the geographical districts from which representatives are chosen either for the State Legislature or for the Federal House of Representatives. Nor does it include the related problems of Gomillion v. Lightfoot, 364 U. S. 339, where “gerrymandering” was used to exclude a minority group from participation in municipal affairs. Nor does it present the question, inherent in the bicameral form of our Federal Government, whether a State may have one house chosen without regard to population. The District Court, however, analogized Georgia’s use of the county unit system in determining the results of a statewide election to phases of our federal system. It pointed out that under the electoral college,8 required by Art. II, § 1, of the Con*377stitution and the Twelfth Amendment in the election of the President, voting strength “is not in exact proportion to population .... Recognizing that the electoral college was set up as a compromise to enable the formation of the Union among the several sovereign states, it still could hardly be said that such a system used in a state among its counties, assuming rationality and absence of arbitrariness in end result, could be termed invidious.” 203 F. Supp., at 169.
Accordingly the District Court as already noted9 held that use of the county unit system in counting the votes *378in a statewide election was permissible “if the disparity against any county is not in excess of the disparity that exists against any state in the most recent electoral college allocation.” 203 F. Supp., at 170. Moreover the District Court held that use of the county unit system in counting the votes in a statewide election was permissible “if the disparity against any county is not in excess of the disparity that exists . . . under the equal proportions formula for representation of the several states in the Congress.” Ibid. The assumption implicit in these conclusions is that since equality is not inherent in the electoral college and since precise equality among blocs of votes in one State or in the several States when it comes to the election of members of the House of Representatives is never possible, precise equality is not necessary in statewide elections.
We think the analogies to the electoral college, to dis-tricting and redistricting, and to other phases of the problems of representation in state or federal legislatures or conventions10 are inapposite. The inclusion of the electoral college in the Constitution, as the result of specific historical concerns,11 validated the collegiate principle despite its inherent numerical inequality, but implied nothing about the use of an analogous system by a State in a statewide election. No such specific accommodation of the latter was ever undertaken, and therefore no validation of its numerical inequality ensued. Nor does the question here have anything to do with the composition of the state or federal legislature. And we intimate no opinion on the constitutional phases of that problem beyond what we said in Baker v. Carr, supra. The present case is only a voting case. Cf. Nixon v. Herndon, 273 *379U. S. 536; Nixon v. Condon, 286 U. S. 73; Smith v. Allwright, supra. Georgia gives every qualified voter one vote in a statewide election; but in counting those votes she employs the county unit system which in end result weights the rural vote more heavily than the urban vote and weights some small rural counties heavier than other larger rural counties.
States can within limits specify the qualifications of voters in both state and federal elections; the Constitution indeed makes voters’ qualifications rest on state law even in federal elections. Art. I, § 2. As we held in Lassiter v. Northampton Election Board, 360 U. S. 45, a State may if it chooses require voters to pass literacy tests, provided of course that literacy is not used as a cloak to discriminate against one class or group. But we need not determine all the limitations that are placed on this power of a State to determine the qualifications of voters, for appellee is a qualified voter.
The Fifteenth Amendment prohibits a State from denying or abridging a Negro’s right to vote. The Nineteenth Amendment does the same for women. If a State in a statewide election weighted the male vote more héavily than the female vote or the white vote more heavily than the Negro vote; none could successfully contend that that discrimination was allowable. See Terry v. Adams, 345 U. S. 461. How then can one person be given twice or ten times the voting power of another person in a statewide election merely because he lives in a rural area or because he lives in the smallest rural county? Once the geographical unit for which a representative is to be chosen is designated, all who participate in the election are to have an equal vote — whatever their race, whatever their sex, whatever their occupation, whatever their income, and wherever their home may be in that geographical unit. This is required by the Equal Protection Clause of the Fourteenth Amendment. The concept of *380“we the people” under the Constitution visualizes no preferred class of voters but equality among those who meet the basic qualifications. The idea that every voter is equal to every other voter in his State, when he casts his ballot in favor of one of several competing candidates, underlies many of our decisions.
The Court has consistently recognized that all qualified voters have a constitutionally protected right “to cast their ballots and have them counted at Congressional elections.” United States v. Classic, 313 U. S. 299, 315; see Ex parte Yarbrough, 110 U. S. 651; Wiley v. Sinkler, 179 U. S. 58; Swafford v. Templeton, 185 U. S. 487. Every voter’s vote is entitled to be counted once. It must be correctly counted and reported. As stated in United States v. Mosley, 238 U. S. 383, 386, “the right to have one’s vote counted” has the same dignity as “the right to put a ballot in a box.” It can be protected from the diluting effect of illegal ballots. Ex parte Siebold, 100 U. S. 371; United States v. Saylor, 322 U. S. 385. And these rights must be recognized in any preliminary election that in fact determines the true weight a vote will have. See United States v. Classic, supra; Smith v. Allwright, supra. The concept of political equality in the voting booth contained in the Fifteenth Amendment extends to all phases of state elections, see Terry v. Adams, supra; and, as previously noted, there is no indication in the Constitution that homesite or occupation affords a permissible basis for distinguishing between qualified voters within the State.
The only weighting of votes sanctioned by the Constitution concerns matters of representation, such as the allocation of Senators irrespective of population and the use of the electoral college in the choice of a President. Yet when Senators are chosen, the Seventeenth Amendment states the choice must be made “by the people.” Minors, felons, and other classes may be excluded. See *381 Lassiter v. Northampton Election Board, supra, p. 51. But once the class of voters is chosen and their qualifications specified, we see no constitutional way by which equality of voting power may be evaded. As we stated in Oomillion v. Lightfoot, supra, p. 347:
“When a State exercises power wholly within the domain of state interest, it is insulated from federal judicial review. But such insulation is not carried over when state power is used as an instrument for circumventing a federally protected right.”
The conception of political equality from the Declaration of Independence, to Lincoln’s Gettysburg Address, to the Fifteenth, Seventeenth, and Nineteenth Amendments can mean only one thing — one person, one vote.
While we agree with the District Court on most phases of the case and think it was right in enjoining the use of the county unit system12 in tabulating the votes, we vacate its judgment and remand the case so that a decree in conformity with our opinion may be entered.
It is so ordered.