U.S. Senator John McCain will remain in Arizona next week to recuperate from a medical procedure that removed a 2-inch blood clot above his left eye, his office announced in a statement on Saturday.

The U.S. Senate will delay its consideration of healthcare legislation while Senator McCain recuperates from surgery, Senate Republican leader Mitch McConnell said in a statement on Saturday.

McCain’s absence cast doubt on whether the Senate would be able to pass the legislation to dismantle and replace Obamacare.
McConnell needs 50 “yes” votes for passage in a chamber the Republicans control by a 52-48 margin.

Repealing and replacing President Barack Obama’s signature healthcare law was a top campaign promise for President Donald Trump and Republicans in Congress.

But two Republican senators have already declared their opposition to revised legislation unveiled on Thursday.