The last high-profile Republican Senate primary fight this year will take place Tuesday in Alaska.

Republicans there will decide who will face Democratic incumbent Sen. Mark Begich in a showdown that could determine which party will control the Senate.

Begich is one of just a handful of Democratic incumbents up for re-election in states that voted for Mitt Romney in 2012, and he’s a top target for the GOP. So picking his opponent is a big deal.

The smart money seems to be on former state Attorney General Dan Sullivan, as recent polls have shown him leading opponents Mead Treadwell and Joe Miller. He has six field offices around the state, and his campaign recently picked up an endorsement from Condoleezza Rice, who served as secretary of state under President George W. Bush.

“We are feeling confident heading into Tuesday’s election,” said Mike Anderson, a spokesman for Sullivan’s campaign.

Treadwell, the state's lieutenant governor, has also said he’s feeling optimistic.

"We’re at a fast gallop,” he said in a statement. “One of the traditional polls that has been a barometer of success is the longstanding Tanana [Valley] State Fair Straw Poll. That poll shows us winning by a strong margin.”

Treadwell has also won support from former astronaut Buzz Aldrin, the second person to walk on the moon.

Mark Begich at his campaign headquarters earlier this month (Photo: AP)
Miller was the 2010 Republican Senate nominee. But after defeating Sen. Lisa Murkowski in the state’s primary, he went on to lose to her after she mounted an unusual but successful write-in campaign.

Though his poll numbers have been less than impressive, Miller has recently picked up endorsements from Sarah Palin and Fox News host Mike Huckabee, former governor of Arkansas.

Justin Barasky, national press secretary for the Democratic Senatorial Campaign Committee, said the Republican infighting has boosted Begich’s chance at winning re-election.

He argued that Miller's presence in the contest has forced Treadwell and Sullivan to tack further to the right than they otherwise might have, and that he expects Ohio native Sullivan’s Alaskan bona fides to be a vulnerability in November.

“That’s a good solid half of why Mark Begich has the lead there,” Barasky said.