By Brendan O'Brien

MILWAUKEE (Reuters) - Wisconsin Governor Scott Walker on Thursday signed a measure into law that eliminates absentee voting on weekends ahead of elections but vetoed a provision that restricted weekday voting hours across the state.

Wisconsin law allows voters to cast absentee ballots by mail or hand them in to their polling places before election day. Supporters have said the new law creates uniform and fair rules, while critics have said it disenfranchises voters.

Walker, a Republican who is seeking re-election, vetoed a part of the bill the majority Republican legislature approved that capped voting at 45 hours per week. Voting will be allowed only on weekdays from 8 a.m. to 7 p.m. at clerks' offices.

Voter rights have become a political and racial flashpoint across the United States. Democrats generally oppose measures that restrict voting, saying they disenfranchise minorities and young people such as college students. Many Republicans back them, saying they are needed to combat voter fraud.

Supporters of the Wisconsin measure said it eliminated an unfair advantage for larger municipalities such as Milwaukee which have the money to keep polls open longer, giving their residents more of a chance to vote.

"The legislation gives local governments the needed flexibility while maintaining fairness in our elections," Republican Assembly Speaker Robin Vos said.

United Wisconsin, a voter advocate group, said it was disappointed that Walker did not veto the entire bill.

"His actions amount to betrayal of trust of the hundreds of thousands of Wisconsin seniors, veterans, students, and working people," executive director Lisa Subeck said in a statement.

(Editing by Matthew Lewis)