While Rick Santorum targets Michigan in a big way, a minor controversy brews in Indiana, where, yesterday, four voters filed official challenges to his candidacy, claiming that he fell eight signatures short in Marion County of the 500-signature-per-congressional-district requirement to appear on the ballot. An election commission will decide whether Santorum’s signatures are adequate — and that commission just happens to be chaired by Dan Dumezich, the co-chair of Romney’s Indiana campaign organization.

“I can be impartial,” Dumezich told the Indianapolis Star on Monday. “It doesn’t present a problem for me. Of course, if someone wants to argue [that he should step aside] I’d listen to it.”

The Election Commission will convene hearings soon to determine whether Santorum met the requirements for placing his name in contention for the 27 “pledged” GOP delegates to be awarded May 8. Another 17 unpledged delegates will round out the contingent for the June statewide Republican convention.

Dumezich, a former state representative who flirted with a 2010 U.S. Senate run to replace the retiring Evan Bayh, said he hopes to convene a hearing soon. “In my mind,” he told the Associated Press, ”I can always maintain my objectivity.”

The self-delusion here is rich, but Dumezich is also in a generally difficult spot: Unless he allows Santorum access, he’ll be accused of partisanship — even if the circumstances justify his decision. Far better to remove himself from this decision to avoid the suspicion altogether. If I were Romney, that’s what I’d want, too. If Santorum’s off the ballot in Indiana and Romney wins, Dumezich’s role in the decision will taint the victory. Santorum’s GOP competitors had already agreed not to challenge his name on the ballot anyway — albeit before he won in Missouri, Minnesota and Colorado and established himself as an actual contender. Still, no candidate wants to be embroiled in ballot wars; they want to win fair and square.