House Republican leaders bluntly warned their Members today that opposing an extension to a popular payroll tax cut is politically unsustainable.

According to a Republican source in the GOP’s weekly conference meeting Wednesday, Speaker John Boehner (Ohio) told his conference that “if you guys think that not extending the payroll tax cut is politically advantageous, you’ve got to be kidding yourself.” But he reassured Republicans that he would look for spending cuts to pay for it.

After the meeting, Boehner told reporters, “You can take to the bank that they will be paid for.”

“We’re gonna continue to try and find common ground on this issue,” Boehner said. “There’s no debate, though, about whether these extensions ought to be paid for. The president called for them to be paid for. Democrats here have called for them to be paid for.”

Likewise, House Majority Leader Eric Cantor (R-Va.) came out strongly in defense of passing the payroll tax cut extension.

According a second Republican, Cantor “laid down the gauntlet,” insisting that “Republicans don’t believe in raising taxes on anyone, especially middle-class families and that everyone should support it.”

Cantor also told Members in the meeting, “We’ll find ways to pay for it” and said that “taxes are a Republican issue and you aren’t a Republican if you want to raise taxes,” the second Republican said.

The pitch seemed to have an effect on at least some Members. One Republican lawmaker, who said he remains undecided on the issue, nevertheless said that “Speaker Boehner and others, to their credit, are talking about offsetting it with cuts” to spending and that many lawmakers are more comfortable with the idea now.

House Budget Chairman Paul Ryan (R-Wis.), who has criticized the proposal as “sugar-high economics” in the past, said he was open to an extension to the payroll tax cut.

“I’m not going to argue for the economic [justification] … because there isn’t one,” Ryan said following the meeting.

“But I’m not against people keeping their own money,” he added.

When asked if he would want it to be fully paid for with cuts to spending, Ryan said simply, “I think it should, yes.”

Still, not all Republicans are convinced. During an open-mic portion of the conference, several Republicans argued that “we don’t have the money [and] some people are saying it robs Social Security,” the first Republican source said.

The undecided Republican lawmaker agreed, saying the tax cut was sold as an economic stimulus plan but has had only minimal effect while imperiling social security.

“It kind of robs Peter to pay Paul,” the lawmaker said.

Though Republicans are calling for the payroll tax cut extension to be paid for, they have historically argued that tax cuts overall have the effect of bringing more money into the federal Treasury and therefore do not need to be offset.

Jonathan Strong contributed to this report.