Washington — Democratic Sen. Jon Tester of Montana said Thursday that President Biden should not seek another term in the White House, becoming the second Senate Democrat to call on the president to drop his reelection bid.

"Montanans have put their trust in me to do what is right, and it is a responsibility I take seriously," Tester said in a statement shared with the Daily Montanan. "I have worked with President Biden when it has made Montana stronger, and I've never been afraid to stand up to him when he is wrong. And while I appreciate his commitment to public service and our country, I believe President Biden should not seek re-election to another term."

Tester is in a tough race to hold onto his seat in November and represents a state that Mr. Biden lost in 2020. He joins Sen. Peter Welch of Vermont in urging the president to exit the race for the White House, though a number of House Democrats have publicly called on Mr. Biden to withdraw.

The president has faced mounting pressure to bow out of the race since the June 27 presidential debate, when his disastrous performance startled many and led to concerns about whether he was fit to serve a second term. Mr. Biden has so far resisted their calls and, in an effort to silence Democrats worried about his prospects in November, held a number of campaign events with core constituencies and participated in several media interviews in recent weeks.

He was sidelined from the campaign trail Wednesday after testing positive for COVID-19 and is isolating at his home in Rehoboth Beach, Delaware.

The drumbeat for Mr. Biden to drop out of the race has continued, and on Wednesday, Rep. Adam Schiff of California became the most high-profile House Democrat to encourage Mr. Biden to "pass the torch." A protege of former House Speaker Nancy Pelosi, Schiff is running for Senate and expected to win in November.

Congressional Democrats also circulated a letter urging the Democratic National Committee to delay an early virtual roll call vote, during which Mr. Biden would be formally nominated for president. The party said the vote will happen in early August, before the start of the Democratic National Convention on Aug. 19.

Melissa Quinn

Melissa Quinn is a politics reporter for CBSNews.com. She has written for outlets including the Washington Examiner, Daily Signal and Alexandria Times. Melissa covers U.S. politics, with a focus on the Supreme Court and federal courts.

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