WASHINGTON—President Biden warned Thursday that the winner of the 2024 election would control the future of the Supreme Court, as he continued to try to tamp down Democrats’ worries about his ability to defeat Donald Trump and demonstrate he was still up to the job.
Biden has acknowledged in private that the coming days will be critical and that he has to prove himself to the American people, according to a person who spoke to him. A week after his disastrous debate performance, top Democrats have urged him to make the case directly to voters and stave off further calls from allies for him to step aside as the Democrats’ nominee, with a crucial television interview set to air Friday.
On his fourth Independence Day as president, Biden was welcoming active-duty military service members to the White House to celebrate the holiday with a barbecue and fireworks viewing on the South Lawn.
The president also held a phone call Thursday with Israeli Prime Minister Benjamin Netanyahu to discuss “ongoing efforts to finalize a cease-fire deal together with the release of hostages” in the war in Gaza, the White House said.
The White House said the two leaders discussed the recent response to the talks from militant group Hamas and noted Netanyahu’s authorization of his negotiators to engage with the mediators “in an effort to close out the deal.” The Israeli leader is scheduled to address Congress later this month.
As questions continued to swirl around the future of the 81-year-old president, Biden argued that the debate performance was an anomaly.
Biden was asked in a radio interview that aired Thursday if Americans should be concerned after last week’s debate. “No, I had a bad debate. But 90 minutes on stage does not erase what I’ve done for 3 ½ years,” Biden told Andrea Lawful-Sanders of WURD in Philadelphia.
The president was blunt in a separate interview with the Earl Ingram Show in Wisconsin, saying, “I screwed up, I made a mistake but I learned from my father, when you get knocked down, you just get back up—get back up. We’re going to win this election.”
Biden said the next president could appoint at least two more justices to the Supreme Court, pointing to the court’s path since Trump’s presidency. “Imagine what that does to the Supreme Court?” Biden asked, arguing that the three Trump-appointed justices had “gutted voting rights” and noting that they overturned Roe v. Wade, the 1973 ruling that had established the right to an abortion.
Trump, in a video posted by his account to his Truth Social media platform, referred to Biden as an “old broken-down pile of crap,” and predicted his opponent would “quit the race.” Trump, who was seated in a golf cart speaking to someone, said that meant he would face Vice President Kamala Harris, whom he called “so bad, she’s so pathetic.”
The president huddled Wednesday with a group of Democratic governors, who said Biden was clear-eyed about what needed to change following the debate. The president expressed the need to be more unscripted and in public more, according to two people familiar with the meeting.
During the private meeting, Govs. Janet Mills of Maine and Michelle Lujan Grisham of New Mexico were vocal in their concerns about Biden’s chances of winning re-election, the people said, and one of the people said the two governors expressed concerns that Trump could win their states. Spokespeople for Mills and Lujan Grisham didn’t immediately comment on the meeting.
The last Republican to carry New Mexico was George W. Bush in 2004. Maine, which awards electoral votes by statewide totals and congressional districts, has been a reliable state for Democrats in presidential elections, but Trump carried the state’s rural second congressional district in 2016 and 2020, winning one electoral vote in both elections.
A Wall Street Journal poll released Wednesday found that Trump has a 6-point lead over Biden among voters nationally, with 80% saying the president is too old to run for a second term. The share of voters who say Biden is too old to run increased 7 points from the Journal’s survey in February. The Journal’s new poll was conducted in the days after the president’s debate last week.
One of Biden’s most important tests will come Friday in an interview with ABC News’s George Stephanopoulos, a former Clinton White House aide who has been with ABC for more than two decades. The recorded interview will air in full on Friday night, ABC said.
The president will also hold a campaign event in Madison, Wis., appearing in an important battleground crucial to his re-election.
The White House told reporters Wednesday that Biden hadn’t had any additional medical exams since his February physical exam. But White House deputy press secretary Andrew Bates said Thursday that “several days” following the debate, “the president was seen to check on his cold and was recovering well.”
In recent days, Biden has called Democratic congressional leaders as well as his biggest allies in Congress to convince skeptics that he is capable of serving another four years. Democratic lawmakers in Congress have raised deep concerns in private about Biden remaining on the ticket. Texas Rep. Lloyd Doggett has called on Biden to withdraw and other lawmakers have gone public with their concerns about the president continuing to be the Democratic nominee.
Rep. Raúl Grijalva (D., Ariz.) told the New York Times that Biden should step aside. Two Democrats from Trump-leaning districts, Reps. Jared Golden of Maine and Marie Gluesenkamp Perez of Washington, said they thought Trump would win the election if Biden were the nominee.
Rep. Seth Moulton (D., Mass.) said in a statement Wednesday that while he has deep respect for Biden, “I have grave concerns about his ability to defeat Donald Trump.” Moulton said beating Trump would require “prosecuting the case in the media, in town halls, and at campaign stops all over the country.” “President Biden needs to demonstrate that he can do that,” he said.
Catherine Lucey and Annie Linskey contributed to this article.
Write to Ken Thomas at ken.thomas@wsj.com
