Independent U.S. Sen. Angus King of Maine will endorse Democratic 2nd Congressional District candidate Emily Cain at two events Wednesday, her campaign said.

Cain, 34, a Democratic state senator from Orono, has touted her history of negotiating with Republicans in her 10 years as a legislator. Her main opponent, Republican Bruce Poliquin, won his June primary by running to the right of his opponent.

King, a freshman senator who caucuses with Democrats in Washington, will make two appearances with Cain on Wednesday – at a manufacturing company in Auburn in the morning and at the University of Maine in Orono in the afternoon, according to a campaign advisory.

“Senator King’s endorsement means so much to me because he is a leader who has always been willing to stay at the table and solve problems for our state and country,” Cain said in a statement. “My record at the State House is the same.”

James Melcher, a political science professor at the University of Maine at Farmington, said the popular senator’s endorsement could help, if only by drawing attention to her bid.

Cain could use that. A Portland Press Herald poll released on Sunday found her 10 percentage points behind Poliquin. Of the 220 people surveyed, 43 percent said they didn’t have enough information to form an opinion on Cain, who also is facing independent conservative Blaine Richardson of Belfast.

King mostly aligns with Democrats, but recently he has endorsed politicians of all stripes in the region.

In August, he endorsed independent gubernatorial candidate Eliot Cutler. But in May, he backed two incumbent U.S. senators from different parties: Republican Susan Collins of Maine and Democrat Jeanne Shaheen of New Hampshire.

Melcher said his endorsement of Cain “is consistent with his other endorsements, in which he puts a premium on moderation and an ability to work across the aisle with other parties, or at least not being too partisan.”

While Cain has made that a key part of her message, Melcher said Poliquin “has emphasized his staunch conservative credentials and has made little about cross-party cooperation.”

During his primary campaign, Poliquin ran as a staunch conservative, beating Kevin Raye, a moderate former Maine Senate president. In one ad, Poliquin’s campaign said Raye’s career read like “a liberal politician’s tale.”

Since then, he has struck a more conciliatory tone, saying he wants to appeal to all voters. Collins has given him money. On Tuesday, Poliquin announced an expected endorsement from the National Rifle Association, a gun-rights group. He is touting it as a sign that his values line up better with the district’s than Cain’s.

In a statement, Matthew Hutson, Poliquin’s campaign manager, said, “Angus King and Emily Cain certainly have one thing in common and that is their support for Obamacare,” or the Affordable Care Act, the federal health care law that’s largely unpopular and that Poliquin opposes.

“On this Bruce Poliquin certainly disagrees, but he doesn’t disagree on every issue, and he looks forward to working with Susan Collins … and with Angus when he serves the 2nd District in Washington,” he said.