(CNN) - The field in the race for New Hampshire's open Senate seat is growing.
Conservative activist Ovide Lamontagne, a 52-year-old Manchester attorney and 1996 GOP gubernatorial nominee, will officially become a candidate Monday for the U.S. Senate seat being vacated by fellow Republican Judd Gregg, who is not running for re-election next year.
Lamontagne is filing a statement of his candidacy with the Federal Election Commission. His campaign also unveiled a new Web site, Ovide2010.com, which highlights his anti-establishment and anti-Washington bid for for the Senate.
"I am running for Senate because I am ready to fight for New Hampshire taxpayers, families and businesses," says Lamontagne in a statement on his website. "I am not the establishment candidate, but, as the independent minded conservative, I am ready to lead the effort to bring fiscal sanity and fundamental reform to Washington once and for all."
Lamontagne becomes the fourth official candidate in the race for the GOP nomination, joining former state attorney general Kelly Ayotte, businessmen James Bender of Hollis and William Binnie of Rye. Rep. Paul Hodes, who represents New Hampshire's 2nd district, is the only Democrat in the race.
Lamontagne has been weighing a run since earlier this year. Fundraising will be his first problem to tackle, as Ayotte brought in $600,000 in the third quarter and her campaign has more than half a million dollars in the bank. Lamontagne has promised his wife he won't use personal money to fund the campaign, which means he'll rely on personal contributions as well as political action committees to pay for his Senate bid.
Lamontagne says he's not worried that Gregg and some members of the Senate Republican leadership recruited Ayotte to run.
"I'm liberated by that," he told the New Hampshire Union Leader. "I don't want to be beholden to the national party or the party bosses. I'll never be the establishment candidate. I'll always be the people's candidate."
Will the battle for the GOP Senate nomination in New Hampshire turn into another NY-23, the congresional contest that grabbed headlines when support from the right for a conservative candidate forced the more moderate Republican candidate out of the race - and allowed the Democrats to win a district they hadn't won in generations?
"Does it ultimately become a major ideological primary? We just don't know at this point," says Stuart Rothenberg, editor and publisher of the non-partisan Rothenberg Political. "To compare the race in New Hampshire to NY-23 is just wishful thinking for the Democrats. It's way too soon to be talking about that."
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