Angus King
Angus King is running as an independent candidate for Olympia Snowe's seat in the U.S. Senate.

After running as an Independent, newly-elected Senator Angus King of Maine has chosen to caucus with Democrats, according to POLITICO.

The former Maine governor's shift leaves Senate Democrats with a 10-seat majority for the first two years of President Obama's second term in office. King said being able to join the majority was the deciding factor in his decision.

“The outcome of last week's election makes the decision relatively easy,” King told reporters in the Capitol Wednesday morning. “In the situation where one party has a clear majority and effectiveness is an important criteria, affiliating with the majority makes the most sense."

If King had chosen to caucus as an Independent, he would have risked being left out of vital Senate committees, groups he's long pushed to be a part of in the past.

“Getting on Finance as a first-year senator without a party I think is a long shot,”King told POLITICO Tuesday.“The principal reason that I was interested is because I think a thorough, major tax reform is going to be part of the deficit reduction.”

While Senate Majority leader Harry Reid (D-Nev.) gave King no assurances about committee assignments, he told the media that he was extremely pleased with King's decision to join the Democratic caucus.

As part of his decision making, King said the Democratic party assured him that he could continue to espouse his independence and not be expected to toe the party line.

During the three-way Senate race for retiring Republican Olympia Snowe's seat, King deflected $4 million spent by Republicans to defeat him.

Few in either party expected the Republicans to court King if he were elected. Only Roy Blunt (R-Mo.)--on behalf of GOP leaders—has had a conversation with King about caucusing.

The Democratic party chose to stay relatively silent during the Maine senatorial race, even refusing to endorse the Democratic candidate, Cynthia Dill. King was the heavy favorite and the party did not want to alienate him if he were to win.

King said recently that he didn't let Republican campaign criticism bother him, and that he doesn't rule out caucusing with the group if they're to gain a Senate majority in the future.

Right now, King says, he's using his Independent position to bolster the premises which he ran on: that he's beholden to neither party, and that he'll use his stance to bring the two sides together.