AUGUSTA, Maine — With Labor Day just a week away, the race for the Maine governor’s mansion is about to get much more contentious — and public.

But Democratic and Republican party leaders also are gearing up for hundreds of legislative races whose collective outcome — while lower-profile than the gubernatorial race — likely will have a dramatic impact on whoever captures the Blaine House this November.

Republicans are hoping to tap into any anti-incumbent fever in the electorate and potential cross-party support for GOP gubernatorial nominee Paul LePage to win control of the state Senate, where Democrats now hold a 20-15 edge.

“I’m optimistic,” said Maine Republican Party Chairman Charlie Webster. “We have at least a 50-50 chance of winning the Senate.”

The odds of a GOP-controlled House are much slimmer; Democrats now hold 95 of the 151 seats. But Webster won’t rule it out, and he believes his party has an opportunity for significant gains this year.

Democrats said they recognize 2010 could be a challenging election cycle, but they have worked hard to field strong candidates.

“We are not taking anything for granted,” said Arden Manning, who is heading up the Maine Democratic Party’s “Victory 2010” campaign, Sunday evening after a major Democratic fundraiser.

All but a handful of races in both the House and Senate feature both Democratic and Republican candidates, and several districts feature three-way or four-way races also involving Green Independent or Independent candidates.

Several Senate races are for open seats in which the senators have either been term-limited out or chose not to seek re-election.

For instance, the race for the District 28 seat now held by Sen. Dennis Damon, D-Hancock, pits two current lawmakers — Rep. Jim Schatz, D-Blue Hill, and Rep. Brian Langley, R-Ellsworth — against former Green Independent Party Chairwoman and gubernatorial candidate Lynne Williams of Bar Harbor.

In central Maine, two-term legislator Rep. Patsy Crockett, D-Augusta, is battling against the well-known mayor of Augusta, Roger Katz, for the seat now held by Senate President and Democratic gubernatorial candidate Libby Mitchell.

Also in central Maine, the surprise decision by Assistant Majority Leader Sen. Lisa Marrache, D-Waterville, not to seek re-election opened up that Senate seat during an election when LePage — the popular Republican mayor of predominantly Democratic Waterville — is running for governor.

Webster believes Republicans have several feathers in their caps this year. First of all, Mitchell’s name at the top of the ballot for Democrats is “a dream for Republicans,” Webster said.

Republicans already are attempting to link Mitchell — a veteran lawmaker who has served as both Senate president and House speaker — to what they see as mismanagement of the state under Democratic leadership. And Webster is hoping that strategy will prompt voters to lean Republican farther down the ballot as well.

“If voters want LePage, they need to send people [to Augusta] to help him change the state,” Webster said.

Webster also said he believes voters are still angry at the majority party over last year’s tax restructuring measure, which was repealed at the ballot box in June. The GOP recruited seven Republican legislative candidates just on that issue, he said.

Democrats, meanwhile, are already busy attempting to link not only LePage but also the entire Maine GOP to the tea party movement that is popular with some conservative or more libertarian-minded voters.

While Manning said involvement of tea party supporters has provided the Republican Party with a boost in the number of volunteers, he believes many moderate Mainers will disagree with some of the more controversial aspects of the tea party movement.

“They are, for all intents and purposes, the Republican Party,” Manning said of the tea party.

Manning said Democrats also have tried harder to field strong contenders in legislative districts that typically go Republican in hopes that the right candidate can overcome political labels.