The Minnesota Supreme Court heard arguments Tuesday afternoon in a lawsuit aimed at keeping the voter ID constitutional amendment off of the statewide ballot. The American Civil Liberties Union of Minnesota, League of Women Voters Minnesota and other anti-amendment groups are asking the court to strike down the ballot question. They claim its wording is too vague and misleading.

Minnesota's reputation as a squeaky-clean state is under attack. The Minnesota Majority, a conservative group that has campaigned for a strict photo ID requirement, put up a billboard near Elk River that says Minnesota is "number one" in voting fraud. Meanwhile, groups on both sides of the issue are plotting strategy in the run-up to the vote.

The Minnesota chapter of the ACLU last month offered a $1,000 bounty to anyone who can show proof of voter impersonation. Now a government watchdog group claims it has court documents that show someone voted fraudulently in the 2008 election.

The league has come out as one of the most vocal opponents to a proposal to require photo IDs at the polls, which has pitted the group against Republicans, some of whom say the advocacy group has become more partisan.

In a shocking upset, the voter ID amendment has failed, and by a sizable margin. With 98 percent of precincts reporting, the "no" votes led by nearly 8 percentage points, MPR says. The measure would have amended the state constitution to require voters to bring photo IDs to the polls.

The American Civil Liberties Union of Minnesota is offering a $1,000 reward to anyone who can find a case of voter impersonation in the state during the last ten years. The group opposes the effort to put a voter ID requirement on Minnesota's ballot. Backers of the idea say it will reduce voter fraud. But the ACLU argues fraud is not a problem here.

If the Republican Senate also passes it, voters in the general election this November will decide whether to amend the state's constitution to require that voters present a valid photo ID before they can cast a ballot.

A final vote in the Senate awaits. The bill would ask voters in November whether to amend the state's constitution to require voters present a valid photo ID before they participate in an election.