Rep. Jim Jordan has sent a letter to colleagues announcing his speakership bid.

"We are at a critical crossroad in our nation's history," he wrote. "Now is the time for our Republican conference to come together to keep our promises to Americans."

Senate Republican leader Mitch McConnell said he is keenly aware of the thankless work it takes to be a Congressional leader as he praised McCarthy in a floor speech.

“I’ve said before, in reference to my own position, that being the leader of your party in the Senate is much like being the groundskeeper at a cemetery. Everybody’s under you, but no one’s listening," McConnell said, adding: “Of course, I doubt that Kevin McCarthy has ever seen himself as above anyone else."

McConnell praised McCarthy's willingness to dive "head first" into worthwhile fights, calling him a trusted and honest partner in leading the GOP caucus.

“He didn’t hesitate to get his hands dirty. When circumstances were tough, he drew on his faith, his family and his belief in American exceptionalism," McConnell said.

“And I’m not sure anyone could have predicted just how much these qualities would come in handy over the past nine months," he said.

-ABC's Mariam Khan

Rep. Jim Jordan, R-Ohio, told reporters Wednesday morning that he is running for speaker of the House -- the first member to publicly throw their hat in the ring.

Jordan, a top Trump ally and chairman of the House Judiciary Committee, has ruled out running for speaker in the past.

Jordan said Wednesday morning that the messages and phone calls of support he has received so far "seems strong."

"I think the key is to unite the conference," Jordan said. "I think I can."

In addition to Jordan, House Majority Leader Steve Scalise has begun making calls to gauge support as has Oklahoma Rep. Kevin Hern.

-ABC News' Katherine Faulders and Arthur Jones

Former President Donald Trump, arriving to court for the third day of his civil fraud trial, commented on the speaker's race -- specifically, the calls from some hard-line conservatives such as Marjorie Taylor Greene for him to serve in the role.

"I'll do whatever it is to help. But my focus, my total focus is being president," he told reporters.

It's not the first time we've heard Trump's name floated for the position. Back in January, amid McCarthy's fraught battle for the gavel, Gaetz actually cast a ballot for Trump during one of the 15 rounds of voting.

It would technically be possible because the Constitution doesn't specify that the person be a current member or member-elect, but it's not likely.

Trump didn't say who he would like to see succeed McCarthy but said, "We have some great people in the Republican Party that could do a great job as speaker."

-ABC's Lalee Ibssa, Soorin Kim and Kendall Ross

From the moment McCarthy was elected speaker, it was clear that his ability to keep that job could depend on Democrats.

To get elected on that 15th ballot in January, McCarthy had to agree to a series of rules that made him a profoundly weak speaker -- including the provision allowing a single member of the House to call for a vote to oust him (the now-famous "motion to vacate"). But while it takes just one member to call for such a vote, it requires a majority to actually remove the speaker.

McCarthy could survive a rebellion from a handful of renegade Republicans -- but he could not survive such a rebellion if Democrats go along with it.

Gaetz has said he expected Democrats to save McCarthy. Many others did too.

As recently as Tuesday morning, House Minority Leader Hakeem Jeffries suggested a way out of this for McCarthy. In an interview on MSNBC, he said House rules should be changed so that a single member could not force a vote on removing the speaker. Jeffries could deliver the votes to save McCarthy's job and the votes to change the rules to make it impossible for Gaetz to pull off a stunt like this again.

But Democrats would have a price for doing that. What would McCarthy offer in return? An end to the impeachment inquiry in President Joe Biden and his family? A guarantee that McCarthy honors the deal he struck on spending with the White House? Power sharing?

McCarthy has developed a cordial relationship with Jeffries, but he signaled no willingness to give Democrats anything in exchange for keeping the job.

In fact, McCarthy's actions have made it virtually impossible for Jeffries to throw him a lifeline. The speaker unilaterally launched the impeachment inquiry and just Saturday infuriated Jeffries by attempting to jam Democrats on a bill to keep the government funded for 45 days.

Back in January -- and again last month on impeachment -- McCarthy showed he was willing to do almost anything to appease his right-wing critics to get and keep his job. That worked for a while -- but it has made it virtually impossible to get Democrats to save him now.

-ABC News Chief Washington Correspondent Jonathan Karl