Sen. Ron Johnson (R-WI) thinks Sen. John McCain’s (R-AZ) recently diagnosed brain cancer and the late-night timing of the vote might have been factors in why McCain ultimately decided to vote against the skinny Obamacare repeal last month.

“Again, I’m not going to speak for John McCain, you know, he has a brain tumor right now. That vote occurred at 1:30 in the morning, some of that might have factored in,” Johnson said, speaking to the radio hosts of “Chicago Morning Answer.”

CNN’s KFILE first flagged Johnson’s comments.

The host asked Johnson to clarify, asking if he really thought the cancer played a role in McCain’s judgment call.

“Again, I don’t know exactly what — we really thought — and again, I don’t want to speak for any senator. I really thought he was going to vote yes to send that to conference at 10:30 at night. By about 1:00 or 1:30, he voted no. So you have to talk to John in terms of what was on his mind,” Johnson said.

A McCain spokesperson responded to Johnson’s comments on Wednesday, calling his remarks “bizarre and deeply unfortunate.”

“It is bizarre and deeply unfortunate that Senator Johnson would question the judgement of a colleague and friend. Senator McCain has been very open and clear abut the reasons for his vote,” the spokesperson said.

McCain ultimately decided to vote against the skinny repeal, joining Sens. Susan Collins (R-ME) and Lisa Murkowski (R-AK) and effectively killing the bill with his vote. He said he wanted Republicans and Democrats to work together on a health care plan and said he supported repealing Obamacare, but he wanted an immediate replacement.

After having surgery to get a blood clot removed, McCain was diagnosed with brain cancer. Days later, he flew back to Washington to vote in favor of a motion to proceed to bring the bill to the Senate floor for debate.

Johnson, for his part, was also a critic of the plan at times, but he stepped in line with his party to support the “skinny” repeal bill. He told the radio hosts that the bills Senate Republicans were considering were “grossly inadequate, particularly the skinny repeal” and called the entire process “awful.”

“It was a political process versus a problem-solving process,” he said.

Johnson released a statement Wednesday afternoon, apologizing for not expressing “sympathy” for McCain.

“I’m disappointed I didn’t more eloquently express my sympathy for what Sen. McCain is going through. I have nothing but respect for him and the vote came at the end of a long day for everyone,” Johnson said.

Listen to the interview below:

This post has been updated to include comments from Johnson and McCain spokesperson.