Dunleavy is done.

Sen. Mike Dunleavy, R-Wasilla, abruptly left the Alaska Senate’s governing caucus on Thursday evening, citing differences with the caucus’ approach to Alaska’s $2.8 billion budget deficit.

“Right now, I am a caucus of one,” he said after joining minority Democrats by voting “no” on the version of the state operating budget approved by the Senate Majority.

That lone vote will have big consequences for both Dunleavy and the majority.

Before Dunleavy’s departure, the Alaska Senate Majority was a supermajority that included 14 Republicans and one Democrat, enough votes to accomplish every major procedural action in the Legislature without any minority support.

Now, the majority will be one vote short of what’s needed to spend from Alaska’s Constitutional Budget Reserve, the multibillion-dollar savings account that it is relying upon to balance the state’s budget. If it can’t get that vote, it can’t enact its budget plan.

Dunleavy’s action also has personal consequences. The Senate operates in what’s known as a “binding caucus.” Members are required to vote in one bloc on budgetary items or they lose their caucus membership.

Members of the majority are rewarded for following the caucus line, even if they disagree with a particular decision. Dunleavy was chairman of the Senate’s State Affairs Committee, and he likely will lose that position because of his budget vote. He’ll also lose some of his legislative staff, and he may lose some of his other committee assignments.

“There’s a price for anything you do,” he said after the vote.

Dunleavy has typically been at the conservative end of the Senate Majority. He voted no on the budget because he believes the state should erase its deficit through service cuts, and not through new taxes or cuts to the Alaska Permanent Fund Dividend.

The Senate Majority’s plan doesn’t include new taxes, but it does include slashing the dividend from an estimated $2,300 this year to $1,000, then diverting some of the Permanent Fund’s earnings to cover the deficit.

“I’ve been the odd man out on the Permanent Fund issue,” he said.

Dunleavy called himself the “odd man,” but he might easily have been joined by others.

Before the final vote on the budget, Sen. Shelley Hughes, R-Palmer, spoke at length about how difficult it was for her to vote “yes,” and she was clearly torn about whether to follow Dunleavy’s action or not.

“For me, it would actually be easier to vote no,” she said before voting yes.

Dunleavy said after the fact that he spoke with Hughes and Sen. David Wilson, R-Wasilla, before making his decision.

“I’m actually glad they stayed in the caucus,” he said, and Hughes confirmed in her floor speech that Dunleavy spoke with her before his decision.

In addition to Dunleavy’s thoughts on the budget this year, it is possible that an event coming in 2018 factored into his action Thursday night.

There have been persistent rumors in the Capitol and elsewhere that Dunleavy may run for governor when Gov. Bill Walker’s first term expires in 2018. (Walker has not said if he will run for re-election.)

“I’m not going to dismiss it,” Dunleavy said of those rumors, “but that’s not what this is.”

Contact reporter James Brooks at [email protected] or call 419-7732.