There’s a widening rift between Republicans in the House and Senate, and continued support for Ukraine is right in the middle of it. Or, looked at another way, the pro-Putin bloc of House extremists is determined to end aid to Ukraine and even shut down the government to do so, even if it means endangering the House Republican majority and the prospects for a GOP majority in the Senate.

Back in July, 70 House Republicans went on record as opposing any more aid to Ukraine, voting for an amendment to the Defense Authorization Act introduced by Republican chaos agent Rep. Matt Gaetz. That amendment was soundly defeated by the majority of Republicans and all Democrats. So it was kind of a freebie and an opportunity to posture for those opposing Republicans: They knew it wouldn’t pass. But that also means that the Freedom Caucus extremists are going to keep pushing for Putin. They’ve declared that defunding Ukraine is just one of their outlandish demands in exchange for allowing us to have a functioning federal government. That demand comes with a blatant threat to House Speaker Kevin McCarthy. The unspoken message is: Give in to us or we’ll force a vote on your speakership.

For his part, McCarthy has predictably been all over the map on Ukraine, telling whoever he’s talking to what they want to hear. He ran for the speaker job on the premise that he would cut off Ukraine funding. When he was in Israel this spring, he insisted, “I support aid for Ukraine,” and added, “We will continue to support—because the rest of the world sees it just as it is.” At the same time, he keeps repeating there will be “no blank check” for Ukraine.

Lining up against McCarthy, Senate Minority Leader Mitch McConnell has laid down his own marker: Ukraine aid, and opposition to Russia, must continue. He’s got the majority of Republicans with him, but there are still obstacles he has to navigate as well.