Update: This post has been updated with newly added co-sponsors of Graham’s resolution.

Sen. Lindsey O. Graham (R-S.C.) introduced a resolution Thursday condemning the House’s impeachment inquiry of President Trump. And while 44 Senate Republicans immediately co-sponsored it, eight others very notably didn’t.

Reports indicated there was legitimate concern about jumping headlong into defending Trump with the evidence still mounting against him. And The Dispatch reported that the resolution actually had to be watered down to gain the support it did get:

Numerous senators voiced concerns about Graham’s proposal. Tom Cotton argued that such a public missive would put vulnerable Republicans up for reelection in 2020 in a difficult spot: sign it, and you’re committing yourself to defend the president; refuse, and you’re making yourself a potential target of Trump’s ire.
In the week since this contentious lunch, Majority Leader Mitch McConnell reportedly worked with Graham to remove some of the more incendiary aspects of his proposed letter related to the substance of the ongoing impeachment inquiry, shifting the focus of the resolution instead to safer process arguments. The result? More than 40 Republican senators have joined as co-sponsors, arguing the Democrat-led House is “abandoning more than a century’s worth of precedent” by “denying President Trump due process.”

Graham has now added to his list of co-sponsors, leaving just three GOP senators who haven’t signed on -- Sens. Mitt Romney (R-Utah), Lisa Murkwoski (R-Alaska) and Susan Collins (R-Maine). But the original list of eight holdouts and hesitant senators was a conspicuous one. And they might be worth watching when it comes to whether Trump’s firewall against removal in the Senate starts to show cracks.

Here’s what we can say about them:

  1. One was Romney, which perhaps isn’t surprising.
  2. Two were the GOP senators facing reelection in blue states: Collins and Cory Gardner of Colorado.
  3. The list included three of the four GOP senators who are retiring: Lamar Alexander of Tennessee, Mike Enzi of Wyoming and Johnny Isakson of Georgia (the last of whom is expected to resign at the end of the year and may not be around to vote in an impeachment trial).
  4. The other two were Murkowski, an occasional holdout in situations like these, and Rob Portman (Ohio), whose place on this list might be the most interesting.

Apart from Romney, many of these members have talked about impeachment in similar terms. They have raised concerns about Trump’s actions, while also tossing in some comments about how it’s too early to impeach or critiques of the Democrats’ process.

“It’s inappropriate for the president to be talking with foreign governments about investigating his political opponents, but impeachment would be a mistake,” Alexander said earlier this month. He added that the 2020 election would be better at deciding. Alexander has also declined to comment further, noting that he would be a juror in a Senate impeachment trial.

Collins has offered similar comments about being a juror, but she was even more critical of Trump’s request for China to investigate the Bidens.

“I thought the president made a big mistake by asking China to get involved in investigating a political opponent,” Collins told Bangor Daily News. “It’s completely inappropriate.”

Collins added hat she didn’t like how House Intelligence Committee Chairman Adam B. Schiff (D-Calif.) has conducted himself. But she also criticized colleagues who were prejudging the evidence.

“I am amazed that some of my colleagues have already made up their mind one way or the other before all of the evidence is in and before the facts are known,” she told USA Today. “I think that’s entirely inappropriate, whether they are for the impeachment or against the impeachment.

Isakson, notably, has encouraged the Senate to investigate these matters.

“I don’t know whether he crossed the lines or not, but I know we’ve got the weight in the intelligence committees to get to the bottom of it,” he said. “They have the subpoena power to do it, and they have the authority to do it.”

Gardner has raised perhaps the most process complaints of the eight, calling the impeachment inquiry a “partisan exercise,” but he too has perhaps cracked the door to the idea that Trump did something wrong.

“We are going to get into an investigation of this. I know you want me to say things before the investigation occurs,” he said recently. “This is about impeachment of the president of the United States.”

Of the eight, Murkowski’s comments might be the most biting. After acting chief of staff Mick Mulvaney last week admitted military aid was held up of because Ukraine hadn’t investigated a conspiracy theory that Trump favors (Mulvaney later recanted), Murkowski offered a sharp comment.

“Yes, absolutely it’s a concern,” she said. “You don’t hold up foreign aid that we had previously appropriated for a political initiative. Period.”

The third retiree, Enzi, has basically only said one word about all of this — “No” — when asked if he had a comment.

Which brings us to Portman. There was a time when Trump actually hailed Portman’s comments about all of this. But two weeks ago, Portman bucked.

“The president should not have raised the Biden issue on that call, period. It’s not appropriate for a president to engage a foreign government in an investigation of a political opponent,” Portman said. He also raised concerns about Trump’s praise for a former Ukrainian prosecutor general and said that “it may have been inappropriate” for Trump to involve Attorney General William P. Barr in the matter. But he added: “I don’t view it as an impeachable offense.”

Portman seems like as good a barometer as any for where this is going. The retirees might have more political leeway, and the vulnerable senators have reason to keep their powder dry. Few have been as upfront about their reservations as Portman, though, and this is a guy who apparently played a significant role in getting Trump to eventually release that military aid to Ukraine, after weeks of holding it up.

Just because a member co-sponsors Graham’s resolution doesn’t mean they couldn’t vote for removal, of course, but this was a conspicuous group to be initially left out.