Alaska Lt. Gov. Mead Treadwell (R) is making some key staff changes on his U.S. Senate campaign, announcing Thursday that he will be cutting ties with his campaign manager and a communications aide.

"I have had to make one of the toughest decision [sic] to this point in our campaign, I parted ways with Adam Jones, Campaign Manager. Rick Gorka, part of the communications team is also leaving," Treadwell said in a statement.

Treadwell did not say why he was making the move. National finance chair Peter Christensen will run the campaign day to day until a new campaign manager is in place.

The shake-up comes as former attorney general Dan Sullivan has emerged as the front-runner in the Republican race. Sullivan's raised heaps of cash -- more than five times as much as Treadwell during the last three months of 2013 -- and recently landed the endorsement of the anti-tax Club For Growth, a group known for spending money in primaries.

"By restructuring our campaign, I know our campaign will be in a stronger position to make Mark Begich a one-term Senator," Treadwell said, referencing the Democratic incumbent.