Should it come to pass that Norm Coleman wins his overtime U.S. Senate battle with Al Franken by one vote, the incumbent can thank a convicted felon who illegally cast his ballot in Minnesota's northern reaches.

Eric S. Willems, of Warroad, broke the law Nov. 4 because he voted while being a convicted felon and on supervised release.

And there appears to be nothing any election official or campaign lawyer can do about it.

"His ballot was inserted into the ballot box along with all of the others that day," said Roseau County Auditor Anne Granitz, whose office is in charge of elections in the county.

Once Willems' ballot entered the machine, Granitz said, it was indistinguishable from any other and there is no way to retrieve it.

Normally, a vote one way or another wouldn't make a difference. However, the state Canvassing Board last month painstakingly scrutinized challenged ballots and carefully weighed "voter intent," adjusting the gap between the two rivals accordingly.

When the board's work on challenged ballots and other contested votes was done this week, the panel said Franken had 225 more votes than Coleman. It's a ruling Coleman is fighting in court, meaning it's still possible the final tally could change.

Willems, convicted in 2004 and imprisoned for having sexual contact with a 15-year-old girl when he was 20, told the Grand Forks Herald that he voted for Coleman. There is little chance there are many others like Willems out there who cast ballots under the same felonious circumstances, said Secretary of State spokesman John Aiken. "I know this is extremely rare." He said that in the 2004 and 2006 general elections, there were a combined three ballots cast illegally in Minnesota by felons.

Willems pleaded guilty in a Roseau court this week to knowingly being an ineligible voter and casting a ballot. That act violates his probation, and state corrections officials will determine his punishment once he is sentenced in Roseau County.

Granitz said Willems, 25, registered to vote at the Lake Town Hall polling station on Election Day. She said the registration form and the roster he signed each included an identical oath: "I certify that I have the right to vote because, if I have been convicted of a felony, my felony sentence has expired (been completed), or I have been discharged from my sentence."

She said, "Every person who registers [swears] to that. ... The wording is very specific."

State corrections spokeswoman Shari Burt said Willems left a voice-mail message on Election Day to tell his supervisory agent that he was going to vote. He then checked back in to say he was back from the polling station and it was then that he was told he had broken the law.

Willems told the Herald he wasn't trying to commit a felony by voting. "I was just excited that the presidential election was coming up and I would be able to vote," he said. "I had never voted in my life. ... I really wasn't aware that I couldn't vote."

Paul Walsh • 612-673-4482