MR. CHIEF JUSTICE WARREN delivered the opinion of the Court.
Appellants and the class they represent are unsentenced inmates awaiting trial in the Cook County jail who, though they are qualified Cook County electors, cannot readily appear at the polls either because they are charged with nonbailable offenses or because they have been unable to post the bail imposed by the courts of Illinois.1 They cannot obtain absentee ballots, for they constitute one of a number of classes for whom no provision for absentee voting has yet been made by the Illinois Legislature. The constitutionality of Illinois' failure to include them with those who are entitled to vote absentee is the primary issue in this direct appeal from a three-judge court.
The specific provisions attacked here, Ill. Rev. Stat., c. 46, §§ 19-1 to 19-3, have made absentee balloting available to four classes of persons: (1) those who are absent from the county of their residence for any reason whatever; (2) those who are "physically incapacitated," so long as they present an affidavit to that effect from a licensed physician; (3) those whose observance of a religious holiday precludes attendance at the polls; and (4) those who are serving as poll watchers in precincts other than their own on election day.2 The availability of the absentee ballot in Illinois has been extended to its present coverage by various amendments over the last 50 years. Prior to 1917, Illinois had no provision for absentee voting, requiring personal attendance at the polls, and in that year the legislature made absentee voting available to those who would be absent from the county on business or other duties. In 1944 absentee voting was made available to all those absent from the county for any reason. The provisions for those remaining in the county but unable to appear at the polls because of physical incapacity, religious holidays, or election duties were added in 1955, 1961, and 1967, respectively.
On March 29, 1967, appellants made timely3 application for absentee ballots for the April 4 primary because of their physical inability to appear at the polls on that election day. The applications were accompanied by an affidavit from the warden of the Cook County jail attesting to that inability. These applications were refused by the appellee Board of Election Commissioners on the ground that appellants were not "physically incapacitated" within the meaning of §§ 19-1 and 19-2 of the Illinois Election Code. On the same day appellants filed a complaint, alleging that they were unconstitutionally excluded from the coverage of the absentee provisions. They requested that a three-judge court be convened to rule the provisions violative of equal protection insofar as the provisions required denial of an absentee ballot to one judicially incapacitated while making it available at the same time to one medically incapacitated; and they sought an injunction to restrain appellee Board "from refusing to grant [appellants'] timely applications for absentee ballots." The District Court granted appellants' request for temporary relief on March 30, before the three-judge court was convened, and ordered the Board to issue ballots to qualified Illinois electors awaiting trial in the Cook County jail.4 Both parties then filed motions for summary judgment, the Board asserting that to honor the applications would subject its members to criminal liability under Illinois law.5
On December 11, the District Court granted summary judgment for the Board, holding that the Illinois provisions extending absentee voting privileges to those physically incapacitated because of medical reasons from appearing at the polls constituted a proper and reasonable legislative classification not violative of equal protection. The case was brought here by appellants on direct appeal, 390 U.S. 1038 (1968), and we affirm.
Appellants argue that Illinois' absentee ballot provisions violate the Equal Protection Clause of the Fourteenth Amendment for two reasons. First, they contend that since the distinction between those medically incapacitated and those "judicially" incapacitated bears no reasonable relationship to any legitimate state objective, the classifications are arbitrary and therefore in violation of equal protection. Secondly, they argue that since pretrial detainees imprisoned in other States or in counties within the State other than those of their own residence can vote absentee as Illinois citizens absent from the county for any reason, it is clearly arbitrary to deny the absentee ballot to other unsentenced inmates simply because they happen to be incarcerated within their own resident counties. Underlying appellants' contentions is the assertion that since voting rights are involved, there is a narrower scope for the operation of the presumption of constitutionality than would ordinarily be the case with state legislation challenged in this Court. See Yick Wo v. Hopkins, 118 U.S. 356, 370 (1886).
Before confronting appellants' challenge to Illinois' absentee provisions, we must determine initially how stringent a standard to use in evaluating the classifications made thereunder and whether the distinctions must be justified by a compelling state interest; for appellants assert that we are dealing generally with an alleged infringement of a basic, fundamental right. See, e. g., Reynolds v. Sims, 377 U.S. 533 (1964); Harper v. Virginia Board of Elections, 383 U.S. 663 (1966). Thus, while the "States have long been held to have broad powers to determine the conditions under which the right of suffrage may be exercised," Lassiter v. Northampton County Board of Elections, 360 U.S. 45, 50 (1959), we have held that once the States grant the franchise, they must not do so in a discriminatory manner. See Carrington v. Rash, 380 U.S. 89 (1965). More importantly, however, we have held that because of the overriding importance of voting rights, classifications "which might invade or restrain them must be closely scrutinized and carefully confined" where those rights are asserted under the Equal Protection Clause; Harper v. Virginia Board of Elections, supra, at 670. And a careful examination on our part is especially warranted where lines are drawn on the basis of wealth or race, Harper v. Virginia Board of Elections, supra, two factors which would independently render a classification highly suspect and thereby demand a more exacting judicial scrutiny. Douglas v. California, 372 U.S. 353 (1963); McLaughlin v. Florida, 379 U.S. 184, 192 (1964).
Such an exacting approach is not necessary here, however, for two readily apparent reasons. First, the distinctions made by Illinois' absentee provisions are not drawn on the basis of wealth or race. Secondly, there is nothing in the record to indicate that the Illinois statutory scheme has an impact on appellants' ability to exercise the fundamental right to vote. It is thus not the right to vote that is at stake here but a claimed right to receive absentee ballots. Despite appellants' claim to the contrary, the absentee statutes, which are designed to make voting more available to some groups who cannot easily get to the polls, do not themselves deny appellants the exercise of the franchise; nor, indeed, does Illinois' Election Code so operate as a whole, for the State's statutes specifically disenfranchise only those who have been convicted and sentenced, and not those similarly situated to appellants. Ill. Rev. Stat., c. 46, § 3-5 (1967). Faced as we are with a constitutional question, we cannot lightly assume, with nothing in the record to support such an assumption, that Illinois has in fact precluded appellants from voting.6 We are then left with the more traditional standards for evaluating appellants' equal protection claims.7 Though the wide leeway allowed the States by the Fourteenth Amendment to enact legislation that appears to affect similarly situated people differently, and the presumption of statutory validity that adheres thereto, admit of no settled formula, some basic guidelines have been firmly fixed. The distinctions drawn by a challenged statute must bear some rational relationship to a legitimate state end and will be set aside as violative of the Equal Protection Clause only if based on reasons totally unrelated to the pursuit of that goal. Legislatures are presumed to have acted constitutionally even if source materials normally resorted to for ascertaining their grounds for action are otherwise silent, and their statutory classifications will be set aside only if no grounds can be conceived to justify them. See McGowan v. Maryland, 366 U.S. 420 (1961); Kotch v. Board of River Port Pilot Commissioners, 330 U.S. 552 (1947); Lindsley v. Natural Carbonic Gas Co., 220 U.S. 61 (1911). With this much discretion, a legislature traditionally has been allowed to take reform "one step at a time, addressing itself to the phase of the problem which seems most acute to the legislative mind," Williamson v. Lee Optical of Oklahoma, Inc., 348 U.S. 483, 489 (1955); and a legislature need not run the risk of losing an entire remedial scheme simply because it failed, through inadvertence or otherwise, to cover every evil that might conceivably have been attacked. See Ozan Lumber Co. v. Union County National Bank, 207 U.S. 251 (1907).
Since there is nothing to show that a judicially incapacitated, pretrial detainee is absolutely prohibited from exercising the franchise, it seems quite reasonable for Illinois' Legislature to treat differently the physically handicapped, who must, after all, present affidavits from their physicians attesting to an absolute inability to appear personally at the polls in order to qualify for an absentee ballot. Illinois could, of course, make voting easier for all concerned by extending absentee voting privileges to those in appellants' class. Its failure to do so, however, hardly seems arbitrary, particularly in view of the many other classes of Illinois citizens not covered by the absentee provisions, for whom voting may be extremely difficult, if not practically impossible.8
Similarly, the different treatment accorded unsentenced inmates incarcerated within and those incarcerated without their resident counties may reflect a legislative determination that without the protection of the voting booth, local officials might be too tempted to try to influence the local vote of in-county inmates. Such a temptation with its attendant risks to prison discipline would, of course, be much less urgent with prisoners incarcerated out of state or outside their resident counties. Constitutional safeguards are not thereby offended simply because some prisoners, as a result, find voting more convenient than appellants.
We are satisfied then that appellants' challenge to the allegedly unconstitutional incompleteness of Illinois' absentee voting provisions cannot be sustained. Ironically, it is Illinois' willingness to go further than many States9 in extending the absentee voting privileges so as to include even those attending to election duties that has provided appellants with a basis for arguing that the provisions operate in an invidiously discriminatory fashion to deny them a more convenient method of exercising the franchise. Indeed, appellants' challenge seems to disclose not an arbitrary scheme or plan but, rather, the very opposite—a consistent and laudable state policy of adding, over a 50-year period, groups to the absentee coverage as their existence comes to the attention of the legislature. That Illinois has not gone still further, as perhaps it might, should not render void its remedial legislation, which need not, as we have stated before, "strike at all evils at the same time." Semler v. Dental Examiners, 294 U.S. 608, 610 (1935).
Accordingly, the judgment of the District Court is
MR. JUSTICE HARLAN and MR. JUSTICE STEWART concur in the result.