WASHINGTON -- Democratic Rep. Lloyd Doggett of Texas on Tuesday became the first sitting Democratic member of Congress to call on President Joe Biden to withdraw from the presidential race, a huge moment for the Democratic Party as Doggett says publicly what many elected officials had been speculating about privately.

鈥淚 represent the heart of a congressional district once represented by Lyndon Johnson. Under very different circumstances, he made the painful decision to withdraw,鈥 Doggett said in his statement. 鈥淧resident Biden should do the same.鈥

Doggett鈥檚 statement magnifies the pressure surrounding the president and his team, who have been trying to tamp down party concerns in the wake of Biden鈥檚 disappointing debate performance against former President Donald Trump last week, and Doggett鈥檚 comments could embolden others to follow suit.

In calling on Biden to step aside, Doggett said the president could help usher in a new generation of leadership to help the party achieve its ultimate goal: defeating Trump.

鈥淩ecognizing that, unlike Trump, President Biden鈥檚 first commitment has always been to our country, not himself, I am hopeful that he will make the painful and difficult decision to withdraw,鈥 Doggett said. 鈥淚 respectfully call on him to do so.鈥

Earlier on Tuesday, Democratic Rep. Mike Quigley of Illinois had signaled an openness to replace Biden as the party鈥檚 presidential nominee.

鈥淚 think his four years are one of the great presidencies of our lifetime, but I think he has to be honest with himself,鈥 Quigley told Kasie Hunt on CNN 鈥淭his Morning.鈥 鈥淭his is a decision he鈥檚 going to have to make.鈥

鈥淲e have to be honest with ourselves that it wasn鈥檛 just a horrible night, but I won鈥檛 go beyond that out of my respect and understanding of President Joe Biden, a very proud person who has served us extraordinarily well for 50 years,鈥 he added.

Former House Speaker Nancy Pelosi, a strong Biden ally, said on MSNBC that the president should be participating in multiple interviews as people evaluate him.

鈥淚 think it鈥檚 essential for them to do that,鈥 Pelosi told MSNBC鈥檚 Andrea Mitchell on Tuesday.

The former speaker, who emphasized it is Biden鈥檚 decision about whether to step aside, said that she has heard 鈥渕ixed鈥 responses to the debate from donors and other people in her Democratic network.

鈥淚 think it鈥檚 a legitimate question to say, is this an episode or is this a condition,鈥 Pelosi said, though she added that the same should be asked of Trump, citing his repeated lies during the debate.

Meanwhile, Democratic Rep. Jim Clyburn of South Carolina, a crucial ally for Biden, said on MSNBC he still supports Biden at the top of the ticket but added that he would support Vice President Kamala Harris if Biden were to withdraw as the Democratic presidential nominee.

鈥淚 will support her if he were to step aside,鈥 Clyburn said when asked what he would do if Biden withdraws, later adding, 鈥淭his party should not in any way do anything to work around Miss Harris.鈥

However, Clyburn reaffirmed his support for Biden. 鈥淚 want this ticket to continue to be Biden-Harris and then we will see what happens after the next election,鈥 he said.

Even more Democrats have been expressing their concerns behind the scenes.

While the Biden campaign and White House have maintained that the president is staying in the race and have chalked up Biden鈥檚 debate performance to a bad night that doesn鈥檛 overshadow his accomplishments, lawmakers from across the party have been reaching out to share their anxieties about Biden remaining at the top of the ticket.

A House Democratic lawmaker told CNN that, 鈥淭here鈥檚 a large and increasing group of House Democrats concerned about the president鈥檚 candidacy, representing a broad swath of the caucus. We are deeply concerned about his trajectory and his ability to win. We want to give him space to make a decision [to step aside] but we will be increasingly vocal about our concerns if he doesn鈥檛.鈥