It was buried halfway through a CNN story, but it went off like a land mine with progressive election watchers. Sen. John McCain (R-Ariz.), who is heavily favored to win reelection in 22 days, campaigned for Sen. Patrick J. Toomey (R-Pa.) with a pledge to oppose any new nominee to the Supreme Court if Donald Trump lost the presidency.

“I promise you that we will be united against any Supreme Court nominee that Hillary Clinton, if she were president, would put up,” McCain told Philadelphia radio host Dom Giordano. “I promise you. This is where we need the majority, and Patrick J. Toomey is probably as articulate and effective on the floor of the Senate as anyone I have encountered.”

McCain's comment appeared to contradict what Republicans have said since refusing to hold hearings on President Obama's nominee, Merrick Garland — that there would be a debate on the Supreme Court after the presidential election. While Democratic candidates for Senate have tried to make hay of the Supreme Court stalemate, conservatives have cheered at how little attention the Garland nomination has received.

Ian Millhiser, a legal writer at the Center for American Progress, was the loudest voice condemning what McCain had said.

“Imagine a world where [late Justice Antonin] Scalia’s seat — and two others — remain vacant for five years because a Republican Senate refuses to confirm anyone named by the president,” wrote Millhiser. “Then imagine that all three of these seats are filled five or nine or thirteen years from today, when Republicans finally manage to gain control of both the White House and the Senate. What reason would Democratic governors have to obey the decisions of such a court?”

Election law academic Rick Hasen chimed in: “This is why Democrats need to retake the Senate if they hope to get a Supreme Court nominee on the Court. I expect if they have even a one-vote majority they will nuke the filibuster if they need to.”

In a statement, McCain's office clarified that the senator would “thoroughly examine the record of any Supreme Court nominee put before the Senate.” But few Republicans have been asked to consider an election outcome that remains quite possible: A Clinton victory with short coattails, leaving Sen. Mitch McConnell (R-Ky.) in charge of the upper house and Sen. Charles E. Grassley (R-Iowa) in command of the Judiciary Committee.

Last week, at a town hall meeting in Davenport, Iowa, Grassley feigned exasperation at a question about Garland. “You had to ask that one, didn't you?” he said. But after explaining why it was good to avoid an election-year SCOTUS battle, Grassley suggested that the fight could start in January.

“We ought to let the people have a voice, and let the new president make a decision,” said Grassley. “So whether Hillary wins, or Trump wins, I think it has to be done on January 20 or after that. And I think our Senate majority leader said the same thing.”

And last month, in a short conversation between votes, Sen. Jeff Flake (R-Ariz.) told The Washington Post that there needed to be Supreme Court votes after the election.

“It couldn't be long,” Flake said. “Some people would say, 'Oh, hold out as long as you can.' But politically, you can't hold off that long. And you shouldn't. I think we ought to move on him as soon as we get to the lame duck. Frankly, we'll be lucky if — assuming Hillary Clinton wins — she appoints him.”