Joe Biden on Monday expressed doubts that Democrats can maintain their majority in the US House of Representatives after Republicans won key races over the weekend.

“I think we’re going to get very close in the House, but I don’t think we’re going to make it,” Biden said at a press conference, dedicated to his meeting with China’s Xi Jinping at the G20 summit, in response to a question about abortion legislation following the midterms. Before the midterms, Biden said that the first piece of legislation Democrats would pass if they kept control of both congressional chambers would codify abortion rights established in Roe v Wade.

“I don’t think they can expect much of anything other than we’re going to maintain our positions [on abortion],” he said. “I don’t think there’s enough votes to codify unless something [unusual happens] in the House.”

Democrats are still largely reveling in their performance in the midterms after retaining control of the US Senate, since many believed the elections were going to favor Republicans. But some sobering news for Democrats has come as more House races were called over the weekend.

As of Monday morning, Republicans have won 212 races and are six seats away from taking on a majority. Democrats have 204 seats, and there are 20 races that still need to be called. On Sunday, Republicans won three key toss-up races in Arizona and California. More races in those states, along with Colorado, New York and Oregon, still need to be called but are predicted to go to Republicans.

“Dems’ dreams of holding the House majority probably died tonight,” Cook Political Report analyst David Wasserman tweeted on Sunday night.

Speaking to CNN on Sunday, Democratic House speaker Nancy Pelosi said: “We’re still alive. But again, the races are close.”

Pelosi still praised Democrats’ overall performance in the election.

“Who would have thought two months ago that this red wave would turn into little tiny trickle, if that at all,” Pelosi said.

Democrats cinched a slim majority in the Senate, after two key wins in Arizona and Nevada, where incumbents Mark Kelly and Catherine Cortez Masto won their races respectively.

With 50 seats, along with Democratic vice-president Kamala Harris’s tie-breaking vote, the Democrats have a majority in the Senate for the next two years. Still, a runoff election in Georgia between incumbent Raphael Warnock and Republican challenger Herschel Walker will determine whether Democrats will win a true majority of 51 seats. The runoff is slated for 6 December.

Far from celebrating what could be their reclamation of the House, Republicans have been experiencing infighting in the days after the election.

Some in the party have started to point their fingers at Donald Trump, who is slated to announce that he will try to retake the Oval Office in 2024. On Fox News, Maryland’s Republican governor, Larry Hogan, called the former president an “800lb gorilla”.

The lieutenant governor of Virginia, Winsome Earle-Sears, once an advocate for Trump, told Fox Business that “the voters have spoken, and they said they want a different leader”.

Discord has also been seen in both chambers of Congress, where Republican leaders have been coming under criticism over the election. The House minority leader, Kevin McCarthy, is slated to run for speaker on Tuesday. But a small fraction of pro-Trump lawmakers said they will withhold their support for leverage.

These conservatives want McCarthy to push for a swath of investigations into Biden, including a potential impeachment proceeding, which McCarthy has shown no interest in. McCarthy will need 218 votes to secure the speaker position.

Senate minority leader Mitch McConnell has also been facing attacks from fellow Republicans, including senators Marco Rubio and Ted Cruz. Florida senator Rick Scott, another Republican, told Fox News on Sunday that McConnell failed to have a plan beyond “talking about how bad the Democrats are”.

“Why would you do that? What is our plan? What are we running on? What do we stand for?” Scott said. “We’re just going to run it on how bad the Democrats are, and actually then they cave in to the Democrats.”