“I bet there won’t be a single Republican vote to raise the debt ceiling at the end of the day,” the Senate’s top Republican said in a radio interview Wednesday morning with conservative commentator Laura Ingraham.

McConnell’s remarks come one day after the Kentucky Republican sketched out a “back-up plan” that would shift the political burden of raising the debt ceiling to President Obama and congressional Democrats, allowing for the borrowing limit to be raised without any Republican votes.

McConnell’s “Plan B” would first need to be approved by both chambers and signed into law by Obama in order to take effect – a prospect that was uncertain at best Tuesday evening, as some lawmakers of both parties balked at the idea.

Congress faces an Aug. 2 deadline by which to raise the $14.3 trillion debt limit, or else the country will default, Treasury Secretary Tim Geithner has said.

Republicans in both chambers remain opposed to any debt-limit deal that would include tax increases, and some members have said that they will oppose any debt-ceiling increase at all. House Speaker John Boehner (R-Ohio) said in an interview with Fox News Channel’s Bret Baier Tuesday evening that as many as 59 House Republicans could vote against increasing the country’s borrowing limit, meaning that the support of House Democrats would become a larger factor in the debt-ceiling calculus.

McConnell told Ingraham on Wednesday that despite Republicans’ opposition to raising the borrowing limit, he believes that the country will not default on its debt obligations. He also dismissed criticism of his back-up plan from some Republican presidential contenders.

“There are always differences among Republicans,” McConnell said. “At the end of the day, we’re going to have a good election next year; it’s going to be a referendum on the president.”

“It’s not going to be a referendum on you?” Ingraham asked.

“No, no,” McConnell responded with a laugh.