While House Speaker Nancy Pelosi and her lieutenants predicted Democrats would expand their majority ahead of Election Day, Republicans are on track for a net gain of seats.
"The voters who turned out in this cycle look a lot more like 2016 than was projected. I want answers and I know you want answers," she added on the call, which ABC News was able to listen to.
Bustos said the committee would do a "post-mortem" on the results to share with members.
"This has been a life-or-death fight for the very fate of our democracy," Pelosi said on the call. "We did not win every battle, but we did win the war."
"You hold your head up high," Pelosi said later in the call. "We helped Joe Biden get that mandate."
Moderates, progressives clash over party message
Rep. Abigail Spanberger, D-Va., a former CIA officer who narrowly defeated her opponent in a moderate suburban district around Richmond, was blunt with her colleagues about the results.
"From a congressional standpoint, it was a failure. It was not a success," she said. "We lost members we shouldn't have lost."
She said Democrats should watch GOP ads and the attacks leveled against members before deciding how to talk about issues.
"We have to commit to not saying the words "defund the police" ever again," she said. "We have to not use the words 'socialist' or 'socialism' ever again."
"If we are classifying Tuesday as a success and we run this way again, we will get f------ torn apart in 2022," she said flatly.
Pelosi disputed Spanberger's characterization of the results as a "failure," noting that Democrats kept the House.
Rep. Rashida Tlaib, D-Mich., a member of the "Squad," pushed back on Spanberger's comments as well, saying the party should study the results before dismissing progressives who are trying to represent their districts.
"Don't blame myself and others who are fighting for issues that matter to our communities," she said. "We need to do a real autopsy and dig through it."
House Majority Whip Jim Clyburn, D-S.C., warned the rhetoric could cost them their last remaining shot at the Senate majority: the Georgia seats that will likely both be headed to a January runoff.
"We have to focus on Georgia for the next several weeks," he said on the caucus call. If Democrats "are going to run on Medicare for All, defund the police, socialized medicine, we're not going to win."
Asked for comment, an aide confirmed Clyburn's remarks on the call and added from the longtime South Carolina congressman, "My comments on today’s private Caucus call are the same sentiments I have expressed for years and publicly reiterated earlier this year. Sloganeering, 'Burn baby burn,' highjacked the movement John Lewis and I helped lead in the 1960s, and slogans like 'Defund the police' could do the same to today's efforts, socially and politically."
Democrats should celebrate 'extraordinary' results of White House race
Rep. Gerry Connolly, D-Va., encouraged Democrats to step back and take a more optimistic look at the results.
"We've got to stop talking in funereal terms ... we have dislodged the biggest threat to democracy ever to sit in the White House," he said. "It's extraordinary. We held the House."
"We need to come out of this conference call full of piss and vinegar," he said. "Yes it's a divided country, yes we're going to unite it. We're going to do the best we can."
"This is a huge win, I know it's not a win across the board. I wanted ... to have a giant moral repudiation of Donald Trump. We did not get that," progressive Rep. Pramila Jayapal, D-Wash., said later on. "Job number one was to get Donald Trump out of the White House and to get Joe Biden into the White House."
"That required us to unify, including progressives, for whom Joe Biden wasn't our first choice," she said.