BANGOR – The race for Maine’s 2nd Congressional District seat picked up steam this week with a Friday visit from President Bush’s top aide and particularly barbed exchanges between the two campaigns.

With Labor Day – the unofficial start of the fall election season – fast approaching, Democratic U.S. Rep. Michael Michaud and his Republican opponent, Brian Hamel, have stepped up their efforts to claim the seat representing northern and eastern Maine.

Hamel, during a Friday fund-raiser featuring Bush chief of staff Andrew Card, sought to paint Michaud as one of the House’s most liberal, anti-business members.

“Every time he says he works for the people of Maine, he’s not … when he votes against their employers,” Hamel told about 100 people in attendance.

Card’s visit is the latest in a string of visits from Bush administration members who have poured into the state’s unpredictable 2nd District, where Bush lost only by a few percentage points in 2000.

But in the Democratic-leaning district, Michaud remains popular, according to recent polls that show him with a comfortable lead over Hamel, the president of the Loring Development Authority in Limestone.

Nevertheless, Republicans at party headquarters in Washington, D.C., insist they see the freshman Democrat as vulnerable.

“We’re going to make a race of it,” said Caryn McLeod of the National Republican Congressional Committee, which has picked Maine’s 2nd Congressional District as among its top targets this year.

This election season, the GOP committee has revived its prominent role in the district, where in 2002 it spent $80,000 in Perry Republican Kevin Raye’s failed effort to win the seat. McLeod said NRCC officials would wait until after Labor Day before deciding which races they would invest in this election cycle.

But in the absence of money thus far, the NRCC has devoted time and ink to the race.

In its latest jabs at Michaud, committee news releases referred to the Millinocket Democrat as an “endangered congressman” and likened him to the party’s presidential nominee John Kerry for spreading “gloom and doom” despite positive economic trends.

But the GOP thinking they can unseat Michaud might be wishful in nature, Christian Potholm, a Republican pollster and government professor at Bowdoin College said, conceding Michaud has done a “good job.”

“Everybody likes to look in the rearview mirror and assume it’s going to be close this time,” Potholm said, noting the relatively narrow margin by which Michaud won the seat in 2002. “But I don’t see where, as an incumbent, [Michaud’s] in any difficulty.”

Erasing the advantage of incumbency can be difficult, a political fact acknowledged by Hamel, who on Friday again challenged Michaud to a rigorous debate schedule in which the two would square off an unprecedented 11 times – once in each of the district’s counties.

The Michaud camp dismissed the request – a common one from political challengers – noting that 10 joint appearances already have been confirmed, although only two were televised debates. A third debate is in the planning stages, according to Michaud spokeswoman Monica Castellanos.

“I think it is enough,” Castellanos said, noting the House is not scheduled to adjourn until early October. “This is ample opportunity for voters to get to know their congressman and his opponent.”

The debate dispute is by no means the only one present in the race, in which each candidate – through registered mail – has challenged the other to disavow any “dirty tricks” when it comes to campaign advertising.

“[H]e has used every excuse in the books as to why he can’t agree to a clean campaign,” Hamel wrote to supporters this week, saying Michaud “isn’t the same straight shooter I am.”

For his part, Michaud responded by asking Hamel to sign an agreement that would prohibit the NRCC and its Democratic equivalent from launching negative attack ads in the race.

“It’s easy to say one supports positive campaigning only to stand back quietly while third party groups do the dirty work,” Michaud wrote.