Angus King, the former governor of Maine who is running for Senate as an independent, is being pressured to announce which party he would caucus with if elected to replace retiring Sen. Olympia Snowe (R).

State Sen. Cynthia Dill, one of the Democrats running for the seat, is circulating a petition asking King to tell Maine voters who he will support.

"The first and arguably most important vote Maine's new U.S. senator will cast will be to choose a leader," the petition, which had 964 signatures Tuesday afternoon, reads.

"The leader of the Senate sets the agenda and is the gate-keeper of all legislation, confirmations and committee assignments. Maine voters are entitled to know whether unenrolled candidate Angus King will vote for Democrat Harry Reid or Republican Mitch McConnell."

“Maine voters deserve to know who their next U.S. senator is going to support to lead the Senate,” Dill told The Hill. “I just can’t imagine an informed electorate would not want to know that until after the election.”

The National Republican Senatorial Committee has charged that King struck a deal with Democrats, but King says that he is a true independent and might not caucus with either party.

"My judgment is going to be based on what's going to make me most effective on behalf of Maine. If I can get away with not caucusing with either side, that's my preference," he told a Maine television station earlier in the month. He since has hired two new campaign staffers -- one from each major party.

King got another rival in the race Tuesday: Maine Secretary of State Charlie Summers announced that he would be the sixth Republican to join the race for the nomination.

10 more election stories from beyond the presidential field:

Money From Outside Missouri Fuels McCaskill Bid [St. Louis Post-Dispatch]

California Sen. Feinstein Shuns Spotlight In Re-Election [McClatchy]

Bob Kerrey Ruled Eligible For Nebraska Ballot [Reuters]

Charles Rangel Fined $23,000 For Campaign Violation [CNN]

California Could Elect First House Independent Since 2004 [Roll Call]

Illinois Congressional Primary Still Not Called A Week Later [Politico]

Montana's Neil Livingstone 'Most Interesting Gubernatorial Candidate in the World' [Mother Jones]

Milwaukee Mayor Could Enter Race To Replace Scott Walker [Minneapolis Star-Tribune]

North Dakota GOP Senate Candidate Skipping Party Convention [AP]

Minnesota Congressional Race Gets New Challenger [Patch]

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