President Joe Biden campaigned in Pennsylvania to reassure voters amid rising calls from some Democrats for him to step aside. Despite concerns over his mental and physical fitness following a poor debate performance against Donald Trump, Biden remains committed to running for a second term.

Five Democratic lawmakers have publicly called for Biden to drop out, and on Sunday, four senior congressmen reportedly joined this chorus. However, Biden insists he is fit to serve and is the only one who can defeat Trump.

Democratic lawmakers are under pressure to either support Biden or urge him to step down. Senators will address the issue in a regular caucus meeting on Tuesday. Biden's next major test is a press conference during the NATO leaders' summit in Washington on Thursday.

Some Democrats, like Senator John Fetterman, continue to support Biden, emphasizing his victory over Trump in the last election. Meanwhile, First Lady Jill Biden is set to campaign in several states, and Biden will prepare for the NATO summit, where he will reassure allies of his commitment.