The House will probably vote Wednesday to impeach President Trump. But that may not be the most significant upcoming vote. The bigger vote may be when the Senate determines the rules for the ensuing trial.

And Sens. Mitt Romney and Susan Collins don’t exactly sound as though they’re preparing to rock the GOP boat — even as GOP leaders signal they’ll push for a Trump-friendly impeachment trial.

Senate Majority Leader Mitch McConnell (R-Ky.) made an extraordinary statement last week, indicating that he will coordinate how the trial will be run with White House counsel Pat Cipollone. And Cipollone may not just be the White House counsel; there are reports he could serve as Trump’s defense attorney at the trial. Democrats and journalists were quick to point out the optics of a trial effectively being run whatever way the defendant wants it to be.

The problem with McConnell’s statement is that he doesn’t have complete control over how the process will be run; that’s because you need a majority vote of the Senate to set the rules. So if a handful of GOP senators objected to his plans — the GOP’s majority is 53-47 right now — they could hold out and force his hand.

In other words, it was the kind of statement to which someone like Romney (R-Utah) or Collins (R-Maine) might object and try to set things on a different course. But in Collins’s case, she took the opportunity to criticize Senate Minority Leader Charles E. Schumer (D-N.Y.) more than McConnell.

Collins objected to Schumer having sent a letter proposing a set of rules of his own.

“I was surprised that he didn’t first sit down with the Senate majority leader and discuss his proposals rather than doing a letter that he released to the press,” Collins said Monday. “The more constructive way would have been for him to sit down with Sen. McConnell.”

She offered a more muted response when asked directly about McConnell, even as she expressed some degree of disagreement.

“Every senator has to decide on his or her own how to approach it," she said. “That would not be the approach that I’ve taken.”

Romney took a different tack. When he was asked about whether he wants White House chief of staff Mick Mulvaney and former national security adviser John Bolton to testify, as Schumer proposed, he basically no-commented about the whole thing.

“It’s not that I don’t have any point of view; it’s just that I’m not willing to share that point of view till I’ve had the chance to talk to others and get their perspectives,” Romney said.

Update: McConnell has now signaled he won’t, in fact, allow new witnesses like Mulvaney and Bolton.

The Senate’s top two leaders could not agree Dec. 17 on whether witnesses should be called at the outset of President Trump’s (The Washington Post)

That doesn’t mean Romney and Collins would necessarily go along if McConnell followed through on letting the White House dictate its own rules. Nor does it mean that McConnell will even go down that route. It seems entirely possible he was saying what he said so that any move toward the middle — even a fair trial — will be seen as a concession. Maybe Romney and Collins eventually take credit for pulling the rules in that direction. If they eventually vote against removing Trump, they could say that at least they made sure the trial was fair.

For now, Americans are somewhat optimistic that it will be. A new Washington Post-ABC News poll released Tuesday morning showed more than 60 percent of Republicans, Democrats and independents said they were at least “somewhat” confident the Senate trial would be a fair one.

One wonders how many of them are familiar with what McConnell said last week, or with Sen Lindsey O. Graham’s (R-S.C.) comments indicating he’s not interested in being a fair juror, because Trump is being railroaded. Collins and Romney don’t seem particularly bothered by those comments, though — or at least bothered enough to speak up.