Friday Briefing: A Make-or-Break Moment for President Biden

President Biden at the NATO Summit in Washington yesterday.Credit…Doug Mills/The New York Times

Biden faces a key test in his campaign

President Biden is ending the three-day NATO summit with a high-stakes news conference that could help rejuvenate his presidential campaign or provide more proof for those calling for him to step aside.

Biden’s allies, doubters and enemies will watch for any verbal stumbles, lost trains of thought or blank stares like the ones that millions of people saw during his debate performance. The news conference is scheduled to start at 6:30 p.m. Eastern. Here’s how to watch it, and you can follow our live coverage here.

Biden has defied growing calls to end his race, even as polls show him falling further behind Donald Trump. Some of his longtime advisers are working on ways to get him to drop out — including by trying to convince him that he can’t beat Trump and that another candidate would have a better chance, those familiar with the plans said. The White House and Biden’s campaign both denied any such internal division.

The Biden campaign is also quietly testing Vice President Kamala Harris’s strength against Trump, in a survey believed to be the first since the debate to measure her viability as a presidential candidate.

Related: An examination of more than two dozen interviews with Biden revealed a pattern of easy questions, that his staff had suggested ahead of time.