Sen. Blanche Lincoln (D-Ark.) had trouble voting Tuesday when she went to cast her primary ballot in Little Rock.
The workers at Lincoln's polling location noted that she had already voted, according to CNN's Dana Bash.
It wasn't an attempt at Election Day trickery. The problem was that Lincoln and her husband had requested absentee ballots, which they hadn't filled out.
"Sen. Lincoln requested an absentee ballot in the event she would be called to Washington for critical votes," Lincoln campaign spokesman Katie Laning Niebaum said in a statement.
The campaign downplayed the mishap.
"Pulaski County Court Clerk Pat O'Brien confirms this is not uncommon among voters who are unsure of their status on Election Day," Laning Niebaum added. "Sen. Lincoln and her husband are happy to cast provisional ballots in person at their home precinct today."