Republican Senate candidate Dan Sullivan is getting some high-profile help. (Photo by Melina Mara/The Washington Post)

To help him deliver his closing argument to voters in one of the country's most contentious Senate races, Republican candidate Dan Sullivan is bringing a political odd couple to Alaska.

Mitt Romney, the GOP's 2012 nominee and tacit head of the party's establishment, and Sen. Ted Cruz (R-Texas), a tea party firebrand, are both jetting to the Last Frontier to boost Sullivan in the runup to Election Day.

Sullivan, campaigning to unseat Sen. Mark Begich (D), will spend this Saturday and Sunday flying around the state with Cruz. The two will headline get-out-the-vote rallies in four of the state's main population areas -- Anchorage, the Mat-Su Valley, Fairbanks and the Kenai Peninsula -- according to a Sullivan campaign source who requested anonymity because the events have not yet been announced.

Next Monday, on the eve of the election, Romney will hold a rally with Sullivan as well as Alaska Gov. Sean Parnell (R) in the Anchorage area, the source said. Romney is one of the GOP's most in-demand surrogates, stumping for candidates in nearly every Senate battleground this fall.

Mitt Romney campaigns for Iowa Senate candidate Joni Ernst in West Des Moines, Iowa, on Oct. 12. (AP Photo/The Register, Mary Willie)

Parnell is campaigning for reelection in a state that leans Republican, but is locked in a tight race against a Democratic-independent unity ticket. Former Alaska governor Sarah Palin (R) recently endorsed the unity ticket of Bill Walker (I) for governor and Byron Mallott (D) for lieutenant governor.

By bringing Romney and Cruz to Alaska, Sullivan hopes to motivate Republican voters to go to the polls. Early voting began in Alaska on Oct. 20, and Begich has a vast and well-financed turnout operation across the state, including targeting Alaska Natives in rural villages.

In 2012, Romney beat President Obama in Alaska, 55 percent to 41 percent. The Sullivan campaign believes Romney's visit will help frame the Senate race in a national context and tie Begich to Obama.

Sen. Ted Cruz speaks at the 2014 Values Voter Summit in Washington. (AP Photo/Manuel Balce Ceneta)

Cruz's visit is designed to help shore up support from grassroots conservatives following the divisive three-way GOP primary in August. Sullivan won the primary with 40 percent of the vote. Joe Miller, a tea party favorite who won the GOP's 2010 Senate nomination, finished second with 32 percent.

The Sullivan campaign hopes Cruz can help drive Miller's supporters -- especially in the Mat-Su Valley, a heavily conservative suburban area outside of Anchorage that includes Palin's hometown of Wasilla -- to the polls for Sullivan.