Updated at 11:49 p.m.

The two major parties chose their candidates for Maine’s open Senate seat, but in this unusual race, both will face an uphill battle against popular former governor Angus King, an independent.

State Sen. Cynthia Dill beat former Maine secretary of state Matthew Dunlap and two other candidates in the Democratic primary. She ran as a progressive Democrat fighting Gov. Paul LePage (R).

On the GOP side, current Secretary of State Charles Summers beat out state Treasurer Bruce Poliquin and four others. Poliquin ran to the right of Summers and lost despite outraising his rival and getting help from the outside group FreedomWorks.

Polls give King a big lead over all of his potential rivals early on. Democrats are not planning to invest much in this race; instead they are hoping to King will caucus with them if and when he joins the Senate.

Republicans are making no such wager, painting King as a closet Democrat and hoping he and the Democrat will split the vote enough to create an opening for the GOP.

Sen. Olympia Snowe (R) is retiring.

Republicans picked Senate nominees Tuesday night in two other contested primaries, with no surprises.

Former Virginia senator George Allen easily won the nomination for his old seat against tea party candidate Jamie Radtke. He will face former governor Tim Kaine (D).

In North Dakota, Rep. Rick Berg beat Duane Sand by a similarly wide margin. He will face former state attorney general Heidi Heitkamp (D).

Both Allen and Berg took about 66 percent of the vote.

And in Nevada, appointed Sen. Dean Heller (R) and Rep. Shelley Berkley officially secured their parties’ nominations in non-competitive races.