While a federal bill requiring proof of citizenship to vote remains stalled in the U.S. Senate, several Republican-led states are advancing their own measures to implement similar requirements for voter registration.

The federal Safeguard American Voter Eligibility Act, which passed the Republican-controlled House on a largely party-line vote, would require documentary proof of U.S. citizenship to register to vote. The legislation has stalled in the Senate due to Democratic opposition and filibuster threats.

South Dakota and Utah have passed legislation creating two-tier voting systems, where voters providing citizenship documentation can participate in all elections, while those without such proof can vote only in federal races. This model follows Arizona's system, implemented after a 2013 Supreme Court ruling that states cannot require citizenship documentation for federal elections. Florida's House has passed similar legislation, while Michigan supporters submitted 750,000 petition signatures for a constitutional amendment.

Federal law already prohibits noncitizen voting in U.S. elections, with penalties including fines, imprisonment, and deportation. Current voter registration requires an oath under penalty of perjury affirming citizenship status. However, supporters of stricter requirements cite rare cases of noncitizen voting, including a 2024 incident where a Chinese student was charged with perjury after illegally registering to vote in Michigan.

Opponents argue that proof-of-citizenship requirements could disenfranchise eligible voters who lack proper documentation. According to a 2024 University of Maryland report, approximately 21 million voting-age citizens lack documentary proof of citizenship or cannot easily obtain it. Legal challenges have been common, with Kansas's similar law blocked by federal courts in 2018 after preventing over 31,000 citizens from registering.

Current legal challenges are pending in New Hampshire and Louisiana, both of which passed proof-of-citizenship laws in recent years. Wyoming's law survived a federal court challenge, though the court dismissed the case on standing grounds rather than ruling on the merits.