An Arkansas judge ruled unconstitutional for the second time in about a week a new law requiring voters to show a photo ID, but said on Friday there was not enough time to prevent officials from applying the law at primary elections this month.

Pulaski County Circuit Court Judge Tim Fox said he was staying his order because to do otherwise would create "turmoil" in thousands of precincts. Last week, he said the law was "void and unenforceable."

Nearly three dozen U.S. states have voter identification measures, according to the National Conference of State Legislatures.

Many Republicans have maintained that the laws are aimed at preventing voter fraud, but several Democrats dismiss the claim, saying no such problem exists and the measures are actually a way of trying to prevent low-income people and minorities, who typically vote for the Democrats, from casting ballots.

The Arkansas attorney general on behalf of the state's election board and the election commission of Pulaski County, the state's most populous, filed separate briefs with the Supreme Court on Friday.

Attorney General Dustin McDaniel's office, representing the state board, said the law protects the integrity of the ballot. But the brief filed by the county election commission asks for the ruling from Fox to remain.

Early voting begins on Monday for the state's May 20 primary.

Arkansas' Republican-led Legislature approved the law last year. Democratic Governor Mike Beebe had vetoed the bill, but the state House and Senate overrode the governor.

(Reporting by Suzi Parker; Writing by Jon Herskovitz; editing by Gunna Dickson)