AUGUSTA – Some swinging-elbow jostling has broken out with a week to go in the crowded race for the Democratic nomination in Maine’s 1st Congressional District.

Iraq war veteran Adam Cote, a former Republican who has sought to portray the six-candidate contest as a battle between himself and front-runner Chellie Pingree, was lambasted in an e-mail Tuesday by the campaign of Portland state Sen. Ethan Strimling as “a Republican in Democrat’s clothing.”

Strimling campaign manager Corey Hascall wrote that Cote has received substantial financial backing from Maine Republicans and support from BIPAC, “a big business group whose board of directors include[s] officials from Halliburton and Exxon Mobil.”

Soliciting donations for Strimling in her “Dear friends” e-mail, Hascall said, “I am writing today to ask that you help us stand up for Democratic values and stop our party’s nomination from being hijacked.”

The Cote campaign, meanwhile, has asserted as recently as Monday that “Cote will focus on economy, Pingree on impeachment.”

Cote, whose criticism by Strimling was presaged by similar comments by another rival, York County District Attorney Mark Lawrence of South Berwick, tied Pingree, Lawrence and Strimling together as advocates of impeaching President Bush and Vice President Dick Cheney.

“This is a defining, substantive issue difference in this election. … Voters have a clear choice on June 10 between real change and even more bitter politics as usual,” Cote said in a statement, noting that the new Congress in January will be at work for little more than two weeks before Bush and Cheney leave office.

Strimling and Lawrence both said over the weekend at the Democratic State Convention in Augusta that they believed lots of potential voters in the June 10 primary election were undecided. The Pingree camp in recent weeks has come to regard Cote, a Portland lawyer, as a major contender in a campaign that also includes former state Senate majority leader Michael Brennan of Portland and Dr. Steve Meister of Winthrop.

Heading into the final full week of the campaign, organizers for Pingree, the ex-chairwoman of Common Cause and former state Senate majority leader from North Haven, appealed to supporters to prepare for a “giant” get-out-the-vote effort beginning this weekend.

“This is critical – in a crowded primary election, EVERY VOTE IS IMPORTANT,” wrote Barbara Burt of the Pingree campaign.

This year’s bid by six-term Democratic Rep. Tom Allen to head off Republican Sen. Susan Collins’ try for a third Senate term has set off a two-party free-for-all for southern Maine’s open congressional seat.

The Republican 1st District contest matches former state Sen. Charles Summers of Scarborough, the ex-regional director of the federal Small Business Administration who spent most of the campaign with the Navy in Iraq, and businessman Dean Scontras of Eliot, who has advocated cracking down on illegal aliens.

The 1st District, which stretches from Kittery up the coast to Camden and extends inland to include Bridgton and Augusta, has been won by a Republican only once – James Longley Jr. in 1994 – since Republican John McKernan moved on after two terms in 1987 to serve two terms as governor.