There was an audible gasp in the Senate gallery this week when Minority Leader Mitch McConnell voted “aye” to cut off a potential GOP filibuster of critical legislation to raise the $17.2 trillion debt ceiling.

A long-time opponent of raising the nation’s borrowing limit without reining in costs elsewhere in the budget, McConnell, R-Ky., was expected to vote “no,” but instead played a critical role in ensuring its passage.

He’s not only a fiscal conservative, but McConnell is also facing a Tea-Party backed primary opponent, making his support of the legislation not only a surprise, but a potential political risk.

But McConnell's move to push the legislation toward passage probably did more to save his re-election bid than hurt it, at least according to the latest polls.

McConnell's primary opponent, businessman Matt Bevin, quickly put out a statement calling his opponent “financially reckless,” for helping Democrats garner the 60 votes needed to bring the bill to the Senate floor.

McConnell voted against final passage of the legislation, which required only a simple majority of 51 votes, but it was his decision to push the bill over the first procedural hurdle that enabled its passage.

“Once again, Mitch McConnell caves to the left, and votes to break conservative filibuster on debt ceiling,” Bevin tweeted after the vote.

But Bevin is trailing McConnell by 30 points in some Kentucky polls, with a survey this week showing McConnell with 55 percent of the vote, compared with 29 percent for Bevin.

At this point, McConnell is expected to handily beat Bevin in the May 20 primary.

McConnell faces a far bigger threat from his left. If he wins the primary, he'll face Democrat Alison Lundergan Grimes in the general election and polls show she could defeat him.

A Wenzel Strategies poll released this week showed McConnell statistically tied with Grimes. It follows a Courier-Journal/Survey USA poll released a few days earlier that showed Grimes ahead by four points.

“It’s really tight,” said Jennifer Duffy, senior editor at the Cook Political Report, which rates political races.

With McConnell’s most serious threat coming from his Democratic challenger, preventing a GOP filibuster of the debt limit bill protects the Republican Party from the onslaught of blame that would come if Treasury Secretary Jack Lew ran out of borrowing authority.

Such a scenario would have mimicked the October government shutdown, led by Tea-Party-backed Republicans who wanted to defund the new health care law in exchange for passing federal spending legislation.

The gridlock resulted in a 16-day government shutdown and an historic drop in the polls for the GOP that directly hurt McConnell, who saw his popularity drop in Kentucky.

A post-shutdown poll by Public Policy Polling found that 60 percent of Kentucky voters opposed the shutdown.

“Nobody learned the lessons of October better than McConnell,” Duffy said.

McConnell’s debt ceiling vote helped to push off the debate on the nation’s borrowing limit until March 2015, long after the election. And it has neutralized a potentially damaging Democratic talking point while protecting his party from what could have been catastrophic damage in the polls if the borrowing limit was not suspended.

Republicans are just six seats away from retaking the majority, with many vulnerable Senate Democrats sinking in popularity because of the troubled rollout of the health law.

If Republicans take over the Senate, McConnell is likely to be elected majority leader.

“Obviously they wanted to be uninhibited to the finish line in terms of keeping the focus on Obamacare,” Republican strategist Ford O’Connell told the Examiner. “I think what McConnell did was smart in terms of Republicans winning the Senate in 2014.”