Lawmakers who vote to support the nuclear deal with Iran should be prepared to face the consequences at the polls next November, according to one of the agreement’s most vehement congressional critics.

“I am convinced that one should vote against this deal because it’s the wrong thing, because it’s absolutely bad for American national security,” Rep. Mike Pompeo (R-Kan.) said on Monday.

{mosads}“But the American people will also, as they most often do, reward elected officials who do the right thing,” he added. “I think they’ll do the same thing here.”

“Even if it’s the case that we’re not able to override the president’s veto … I still think it’s very, very important for every member of Congress to put their marker down on this,” said Pompeo, who has become one of the most passionate opponents of the deal in the House. 

The comments come amid signs that Democrats are increasingly falling in line to support President Obama on the agreement. Although Republicans appear nearly unified in their skepticism of the deal, only a few Democrats have joined them.

Top GOP lawmakers including Senate Majority Leader Mitch McConnell (R-Ky.) have begun to concede that they may ultimately fail in scuttling the agreement, which imposes restrictions on Iran’s nuclear powers in exchange for the lifting of sanctions. Meanwhile, more and more Democrats have expressed support for the deal in recent days, potentially providing a backstop to uphold a presidential veto.  

Yet the remarks from Pompeo make clear that critics of the agreement are going to use the congressional vote as leverage in future fights — even if they can’t ultimately block it from going forward.

“I do think the more members of Congress who put their marker down on the side for protecting American national security, the more likely it is that the next president — whoever that might be — has the capacity to undo what will at best be an administration that took a deeply minority position in an attempt to placate the ayatollahs,” Pompeo said on Monday.

“There should be no free passes on this.”

If lawmakers like Pompeo are stymied from blocking the agreement with Iran, multiple lawmakers have said that they will quickly turn to extending sanctions on Iran.

Earlier this year, Sens. Mark Kirk (R-Ill.) and Bob Menendez (D-N.J.) introduced a bill to renew expiring sanctions for another 10 years. Any efforts to impose new sanctions would likely mirror that bill, Pompeo said.