There are few Republicans more respected in New Hampshire than former Gov. John H. Sununu, but it’s unclear whether his endorsement will be enough to help Juliana Bergeron become the state GOP’s next leader.

Sununu, the outgoing chairman, endorsed Bergeron, the Cheshire County GOP chairwoman, amid an intensifying challenge from a tea party activist.

“I am absolutely convinced that Juliana Bergeron is the best person for the job,” Sununu said in a Monday afternoon conference call.

But local conservatives and some key party leaders aren’t so sure. Dover businessman and tea party activist Jack Kimball also is running for the unpaid position, which is largely responsible for fundraising, messaging and unifying the party. The state GOP is as strong as it’s ever been, with Republicans having won both House seats, held an open Senate seat and achieved massive gains in the 2010 midterms.

And the next leader could play a prominent role in the nation’s first presidential primary, set for little more than a year from now.

But both the state Speaker and Majority Leader have already thrown their support behind Kimball. Sununu, who also previously served as the White House chief of staff, acknowledged that there are differences among the 492 New Hampshire Republicans who will meet Jan. 22 to elect a new leader.

“This is a great Republican Party right now. This is a united Republican Party,” Sununu said. “All I’m concerned about is people wanting to slice it up into different factions.”

Sununu criticized recent “mailings” from Kimball supporters that attacked Bergeron for not being conservative enough, among other things. One of them targeted Bergeron for a Christmas card delivered to supporters.

“I’ve been a little disappointed about the divisive comments made by Jack’s supporters,” Sununu said. “I think that does Jack a disservice.”

The Christmas card, signed by Bergeron, features a quote from the Bible and this blessing: “May the Spirit of Christmas Warm Your Heart and Your Home.”

“No, it doesn’t ask for my vote, or anything else, but why ELSE would she send me a Christmas card, for the very first time, other than to engender a positive political feeling towards her name?” Skip Murphy, a voting member of the New Hampshire Republican State Committee, complained in a posting on a local blog. “I do consider this crass, cynical, and political self-aggrandizement.”

Sununu said that he met with Kimball to talk about his interest in the position, adding that he has a more substantial relationship with Bergeron, who visited the party headquarters regularly in recent months and has a deep understanding of the responsibilities involved.

“We’re talking about a need to raise hundreds of thousands of dollars each year,” Sununu said. “Hundreds of thousands of dollars each year.”

“I am honored to have his confidence and support, and I pledge to build on the strong committee structure that we have in place,” Bergeron said of Sununu in a statement released after the conference call.

“Governor Sununu will be a difficult act for any Republican to follow, but our party needs to continue its efforts to defend our conservative majorities and defeat the Democrats in the upcoming presidential election,” she continued. “As party chairman I will maintain a strong relationship with our conservative grassroots community, effectively manage state committee operations and protect our Party’s conservative platform.”

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