[cnn-photo-caption image= http://i2.cdn.turner.com/cnn/2010/images/05/05/art.nh.ad.jpg caption="Sen. Tom Coburn has endorsed New Hampshire Senate candidate Kelly Ayotte."]
Washington (CNN) - The New Hampshire Republican hoping to keep an open Senate seat in GOP hands picked up the endorsement of another out of state conservative on Friday.
Republican Sen. Tom Coburn of Oklahoma announced his support for Kelly Ayotte, the former New Hampshire Attorney General who also has the backing of former Alaska Gov. Sarah Palin.
"I look forward to having Kelly Ayotte join us in the Senate next year to help defend the Constitution's limitations on federal power and to fight for the fiscal survival of our country," Coburn said in a statement. "She has the experience, the commitment and the integrity to be a strong force for reducing spending, protecting freedom and making government effective yet manageable."
Ayotte has three opponents in the GOP primary, but the race has shaped up as a battle between her and Bill Binnie, a millionaire businessman who has loaned huge chunks of cash to his own campaign.
Palin's July endorsement of Ayotte got a chilly reception from one of the state's most conservative and influential newspapers, a reaction not uncharacteristic of a state known for its political independence.
Shortly after Palin's endorsement, a blistering Op-Ed on the front page of the New Hampshire Union-Leader by publisher Joseph McQuaid said Palin knows little about the Granite State and even less about its residents. Earlier this week, the paper endorsed Ayotte rival Ovide Lamontagne.
New Hampshire voters will decide the Republican Senate nominee in the state's September 14 primary.