Speaker Kevin McCarthy’s (R-Calif.) vow to block Rep. Ilhan Omar (D-Minn.) from sitting on the House Foreign Affairs Committee has hit an early snag: He may not have the votes to do it.

Omar, one of three Muslims in Congress, has been a controversial figure on Capitol Hill for her sharp criticisms of the Israeli government and its human rights record. Republicans have said she’s crossed a line into antisemitism, and McCarthy’s case for booting her from Foreign Affairs rests on that accusation.

But McCarthy has a math problem to solve, one that could prove an early test of his ability to keep his narrow majority united and fulfill a long-running vow.

Democrats are rallying behind Omar, which could force GOP leaders to rely entirely on their own members if they’re to succeed. 

“There’s already two Republicans that have indicated that they won’t vote to put her off, and I think others will come aboard also,” said Rep. Gregory Meeks (N.Y.), the senior Democrat on the Foreign Affairs Committee, who is lobbying Republicans on Omar’s behalf.