WASHINGTON — Democrat Jon Hinck is heading north Nov. 12 to make official his bid to win the U.S. Senate seat held by GOP Sen. Olympia Snowe of Maine.

Hinck, a state representative from Portland, will announce his candidacy during an event and speech at the University of Maine in Orono, a source close to the Hinck campaign said.

Hinck’s official entrance into the race sets up a Democratic primary pitting Hinck against former Maine Secretary of State Matthew Dunlap, who is also a former state representative from Old Town.

Dunlap already has filed his Senate campaign organization papers with the Federal Election Commission, and is expected to hold his first public campaign event soon, as well. Both Dunlap and Hinck have been eyeing a race against Snowe for months.

Snowe is running for a fourth term, having won reelection in 2006 with 74 percent of the vote. Snowe is being challenged from the right in the GOP primary by two tea party affiliated candidates, Scott D’Amboise of Lisbon Falls and Andrew Ian Dodge of Harpswell.

Snowe is currently well ahead of both her primary challengers and the two Democrats seeking the nomination to run against Snowe in the general election, according to a poll of Maine voters conducted Oct. 28-31 by Public Policy Polling. PPP is a national Democratic polling firm that notes polling expert Nate Silver of the New York Times found that its surveys in 2010 actually exhibited a slight bias toward Republican candidates.

Hinck, who is giving up a run for a fourth term in the Maine House to seek the U.S. Senate seat, is leaving Portland to make the official announcement of his candidacy for several reasons, according to the source close to his campaign.

For one thing, it’s a home football game that day – versus Massachusetts – for the Black Bears, who are having a great season, and Hinck and his supporters can go to the game after the 11 a.m. campaign event concludes, the source quipped.

More seriously, Hinck is trying to show that he is a candidate for the entire state, not just southern Maine, the source said.

He also intends to highlight his stance on public education and the importance of devoting time and academic resources to technology innovations in areas such as alternative energy sources like wind power, the source said. Hinck will tout some of the alternative energy research being done at the University of Maine as examples of the type of initiatives that are crucial to the state’s future economic well-being.

Hinck wanted to hold off on an official campaign event until Nov. 12 because he didn’t want to distract from next week’s election and the bid that Hinck favors to repeal the new state law banning same-day voter registration, the source said.

Hinck is an attorney in Portland whose practice includes a focus on litigation involving consumer and environmental issues. He has worked for the Natural Resources Council of Maine and was a co-founder of the environmental group Greenpeace USA.

MaineToday Media Washington Bureau Chief Jonathan Riskind can be contacted at 791-6280 or at: jriskind@mainetoday.com Twitter: Twitter.com/MaineTodayDC.