Republican primary rivals Clint Didier and Paul Akers are teaming up in the race for Sen. Patty Murray's (D-Wash.) seat. The two have been fighting for oxygen in a Republican primary against leading candidate Dino Rossi (R). 

Didier and Akers are planning to use joint forums and radio ads in an attempt to gain some traction against Rossi, who has the backing of most of the state and national Republican establishment. 

Their message: the party establishment is trying to dictate the Republican nominee. 

A major stumbling bloc for that message is the endorsement Rossi won Thursday from Sen. Jim DeMint (R-S.C.). DeMint has inserted himself in a number of Republican primaries this campaign season and has not made a habit of backing the so-called establishment pick. 

"Dino Rossi is a principled conservative who will help us take our country back. He will fight to stop the massive spending, bailouts, and debt that are bankrupting our country," DeMint said in a statement. "The Senate Conservatives Fund will do everything it can to help Dino Rossi. We're going to make sure voters in Washington hear his message and that freedom-loving Americans across the country support his campaign."

DeMint is backing Republican Ken Buck in Colorado's Senate primary. He's also backed Rand Paul in Kentucky, Mike Lee in Utah and Sharron Angle in Nevada this primary season. 

Didier is backed by Tea Party forces in the state and has the endorsement of former Alaska Gov. Sarah Palin.