WASHINGTON ― House Minority Leader Nancy Pelosi is suddenly in a fight for her political survival as a group of Democratic detractors is preparing to block her ascent to the speakership.

About a dozen incumbent Democrats and a half-dozen incoming Democrats are preparing a letter pledging to not support Pelosi on the House floor for speaker. The members also intend to note another contingent of Democrats who privately say they won’t support the longtime California Democrat but won’t sign the letter, according to Rep. Tim Ryan (D-Ohio), one of the ringleaders of the effort to block Pelosi.

Sources familiar with the letter say there are currently 17 names on it, but the group is trying to get more than 20 members before releasing it. Currently on the letter, though not certain to stay on it, are:

- Tim Ryan (D-Ohio)

- Seth Moulton (D-Mass.)

- Kathleen Rice (D-N.Y.)

- Ed Perlmutter (D-Colo.)

- Kurt Schrader (D-Ore.)

- Filemon Vela Jr. (D-Texas)

- Marcia Fudge (D-Ohio)

- Bill Foster (D-Ill.)

- Brian Higgins (D-N.Y.)

- Stephen Lynch (D-Mass.)

- Linda Sanchez (D-Calif.)

- Jim Cooper (D-Tenn.)

- Jeff Van Drew (D-N.J.)

- Joe Cunningham (D-S.C.)

- Max Rose (D-N.Y.)

- Anthony Brindisi (D-N.Y.)

- Ben McAdams (D-Utah)

There is another contingent of Democrats ― including Conor Lamb (D-Pa.), Dan Lipinksi (D-Ill.), Ron Kind (D-Wis.), Abigail Spanberger (D-Va.), Jason Crow (D-Colo.), Haley Stevens (D-Mich.), Elissa Slotkin (D-Mich.), Mikie Sherrill (D-N.J.) and Andy Kim (D-N.J.) ― who are seen as likely to vote against Pelosi, but who also are hesitant to sign the letter.

For Pelosi allies, keeping the number of names on the letter limited is a key to her survival, as more members publicly pledging to not support her would be a nail in the coffin.

But Pelosi also has a number of ways she could wrangle the speaker’s gavel even if a dozen and a half members pledge to oppose her. For one, Democrats could make a new rule binding every member to vote for the Democratic nominee. Rule changes associated with that idea are already under consideration, and there’s some thought that Pelosi may try to formalize rules so that Democrats have to vote for her, though many members question how this strategy would work. (Would they kick out the members who don’t vote for the Democratic nominee? Would they still have a majority?)

There’s also the thought that some Republicans could vote “present,“

thus lowering the threshold for Pelosi. But that presents its own challenges. In effect, Republicans would have veto power over the speaker and Pelosi would not be negotiating from any position of strength.

The way the speaker election works is that a candidate first gets the nomination behind closed doors during the Democratic Caucus meeting. That is the easiest hurdle to clear. A candidate only needs a majority of their party for the speaker nomination, and Pelosi has that part essentially locked up.

The hard part is the floor vote, when a candidate needs a majority of the House: 218 of the 435 members. That number includes Republicans. While we don’t know the exact breakdown of the House yet, it’s likely to be around 234 Democrats and 201 Republicans ― give or take a couple of members on both sides. If the number is 234 Democrats, Pelosi can lose only 16 Democrats if every member votes.

The trick for Pelosi would be to get some of her Democratic opponents ― or Republicans ― to vote present. That would lower the threshold for her election. In effect, a present vote would be a half-vote for Pelosi.

But the Democrats who say they are opposed to Pelosi are already swearing they won’t vote present. If Pelosi can’t convince some of those Democrats who oppose her to vote present, she has a real problem.

The anti-Pelosi members are working to gather as many names as possible as quick as possible, as they believe the longer they remain in the shadows, the more likely it is that Pelosi could flip some of their members.

But Pelosi’s opponents also told HuffPost they think the actual number of Democrats who do not want to vote for Pelosi is much larger than anyone anticipates, and they remain confident she doesn’t have the votes.

Ryan, who ran against Pelosi to be minority leader at the end of the last Congress, told reporters Wednesday that he was certain Pelosi didn’t have the votes, and multiple members who support Pelosi even told HuffPost on the condition of anonymity that they believe she is in trouble.

One of the members pointed to Pelosi’s minority leader race in 2016 with Ryan in which he received 63 votes from his Democratic colleagues to Pelosi’s 134. This member said Pelosi didn’t get the message when one-third of the caucus voted for a “backbencher.”

But if Pelosi didn’t get the message before, she and her team are certainly working now to try to tamp down the revolt and swing the incoming Democrats from no to yes ― or at least to “present.”

Pelosi’s allies all readily point out that “you can’t beat somebody with nobody,” but Pelosi’s opponents are testing that idea. In fact, they seem to think their movement is strengthened without a clear alternative.

The idea is that, once Pelosi knows she can’t win, she will step aside and there would be a new race for the speaker position.

To that point, one office for a prominent Democrat already reached out to HuffPost to suggest that their boss is well-positioned to become speaker if Pelosi can’t get the votes.

Members believe ― for good reason ― that there would be a rush of candidates for the speaker job if Pelosi stepped down, potentially including Minority Whip Steny Hoyer (D-Md.), Assistant Minority Leader Jim Clyburn (D-S.C.), Democratic Congressional Campaign Committee Chairman Ben Ray Lujan (D-N.M.), Barbara Lee (D-Calif.) and Hakeem Jeffries (D-N.Y.).

Ryan, in an effort to deflect criticism that the anti-Pelosi Democrats are just trying to knock off a woman from a leadership role, repeatedly said Wednesday that he’d like to see another woman become speaker, and he has pointed to four women: Marcia Fudge (D-Ohio), Kathleen Rice (D-N.Y.), Karen Bass (D-Calif.), and Cheri Bustos (D-Ill.). (Fudge and Rice are both also anti-Pelosi.)

Moulton has also been strongly pushing Fudge, who is a former Congressional Black Caucus chairwoman.

The anti-Pelosi group is expected to release its letter by the end of the week, though Ryan also said they would hold the letter as long as they were still getting new signatures. Ryan, Moulton, and Perlmutter are the members loosely organizing the letter, and they’re checking in mostly with the new Democrats to make sure they won’t flip under pressure.

But Ryan also assured reporters Wednesday that there were more Democrats than just those who will be on the letter who intend to vote against Pelosi ― they just don’t want the scrutiny associated with revealing themselves.

Still, Pelosi says she is confident she can survive.

Exiting a caucus meeting this morning, Pelosi said she could stop and take questions.

“I’m a busy person,” she said. “I will be speaker of the House no matter what Seth Moulton says.”

CORRECTION: A previous version of this story misstated the number of House seats Republicans are projected to have in the next Congress.