Republicans in Washington are coalescing around President Trump as he faces an impeachment investigation over allegations that he used his presidential authority to get Ukraine to help him politically. But there are cracks.

1. The all-in Trumpers

This group defends Trump at all costs. But the more serious these allegations get, the more they are resorting to factually misleading or incorrect statements about the allegations, and/or unproved theories, and/or discrediting the anonymous whistleblower, and/or focusing on the Democratic face of the investigation, House Intelligence Committee Chairman Adam B. Schiff (Calif.).

Typical member: This group includes some of the most high-profile members of Congress, such as House Minority Leader Kevin McCarthy (Calif.) and chairmen of key committees, such as Senate Judiciary Chairman Lindsey O. Graham (S.C.) and Homeland Security Chairman Ron Johnson (Wis.). Making up the backbone of this group are Freedom Caucus members who long ago aligned themselves with Trump and his base, such as Reps. Jim Jordan (Ohio) and Mark Meadows (N.C.)

The most notable member is Senate Majority Leader Mitch McConnell (R-Ky.) His campaign launched a Facebook ad shortly after House Democrats embraced an impeachment inquiry where he says: “The way that impeachment stops is a Senate majority with me as majority leader.”

Typical statement: To issue broad denials for Trump that don’t specifically address the allegations.

2. The silent majority

This where most Republican lawmakers are. They would rather not have to comment on allegations that some of them privately find disturbing because they don’t want to be seen as turning on the president and his base. Their silence is aided by the fact Congress is on a two-week recess.

Typical member: Rank-and-file House and Senate Republicans, as well as Republicans facing potentially tough reelections next year in races where they need a lot of Republican support to win, like Sens. Cory Gardner in Colorado and Martha McSally in Arizona.

Typical statement: Well, they’re not saying much. The Washington Post’s Robert Costa and Philip Rucker talked to people in some of these lawmakers’ inner circles and found out why:

A Republican strategist who is close with several senators and spoke on the condition of anonymity to share a candid assessment called the situation “a disaster.” This consultant has been advising clients to “say as little as possible” about impeachment developments to buy time.

3. The kind-of critics

This group has publicly expressed concern that Trump raised former vice president Joe Biden with foreign leaders, as in a July call with Ukraine’s president or publicly to China last week. Some members have said that House Democrats are right to investigate a whistleblower complaint. If there were to be bipartisan support for Trump’s impeachment, it would probably come from these members, who are out in front of the rest of their party.

Typical member: This group is small but growing. It includes half a dozen Republican senators, such as Sens. Susan Collins (Maine), Rob Portman (Ohio), Ben Sasse (Neb.), John Thune (S.D.) and Patrick J. Toomey (Pa.).

It also includes a handful of House Republicans, such as Rep. Mark Amodei of Nevada, who was the first to say he supported Democrats’ inquiry. But he almost immediately walked it back to clarify he doesn’t support Trump’s impeachment; he just thinks it’s a good idea to figure out the facts first. The New York Times’s Sheryl Gay Stolberg has a good rundown of all the members of this group.

Typical statement: “I thought the president made a big mistake by asking China to get involved in investigating a political opponent,” said Collins, who is facing a competitive reelection next year. “It’s completely inappropriate.”

Toomey told the Pittsburgh Post-Gazette that Trump’s call with Ukraine’s president was “inappropriate” but said he has seen nothing so far that “rises to the level of removing President Trump from office and reversing the results of an election.”

4. The critic

Out of 252 Republican members of Congress, this group is made up of one member: Sen. Mitt Romney (Utah). Romney got elected to the Senate last year after tempering his criticism of Trump. He has since spoken out against the president on a number of issues, most forcefully with these latest allegations.

But he is alone right now. Trump has noticed, taking whacks at Romney in a way that will certainly get all the other Republicans on this list to notice, as well.

JM Rieger contributed to this analysis.