HARRISBURG — A judge considering a challenge to a politically charged Pennsylvania law that requires voters to show photo identification suggested Thursday he might strike part of it so that someone who doesn’t have a valid ID at the polls can cast a provisional ballot that will still count.

Commonwealth Court Judge Robert Simpson made the suggestion toward the end of a hearing on the issue, and lawyers for the plaintiffs seeking to halt enforcement of the entire law before the Nov. 6 presidential election quickly protested it, saying it could cause even more problems and confusion.

Simpson said he was seeking a way to target “the part of the act that’s the offending activity, the disenfranchising part.” Under the new law, someone who does not have a valid ID at the polls can cast a provisional ballot, but it won’t count unless they show a valid photo ID to county election officials within six days of the election.

What Simpson seems to be considering would excuse a voter without valid ID at the polls from having to get it and show it later.

The constitutionality of the law is not a question in front of Simpson. Instead, the judge is under orders from the state Supreme Court to issue an injunction of the law for this year’s election if he finds the state has not met the law’s promise of providing free and easy access to a photo ID or if he believes it will prevent any registered voters from casting a ballot.

Simpson must rule by Tuesday, just five weeks before the election.

If Simpson follows through on his suggestion, it would effectively hand a victory to the state by leaving most of the 6-month-old law intact for the election, and the entire law intact for every election afterward.

The plaintiffs’ lawyers contend the state’s stumbling attempts to comply with the law have obstructed efforts among voters to get a photo ID, violated the spirit of the law, and ensured that some people will be unable to exercise their right to vote, particularly young adults, poor people, minorities, the elderly and the disabled.

The plaintiffs — including the League of Women Voters of Pennsylvania and the Pennsylvania chapter of the National Association for the Advancement of Colored People — say many voters still are unaware of the new law.

Among the toughest in the nation, the law has sparked debate over voting rights and has become a partisan lightning rod in the contest between Democratic President Barack Obama and Republican presidential nominee Mitt Romney for Pennsylvania’s prized 20 electoral votes.

Witnesses testified of making numerous trips to driver license centers to confront clerks who seemed equally confused by a bureaucratic maze.