Biden listened, but he wasn’t convinced.

Biden and a small circle of aides got as far as the basics of a plan in the summer and early fall of 2015. He wrote an announcement speech that he’d read to people, in person and over the phone. That meeting in Washington with Plouffe stopped him, at least for a moment. The prospect of losing started to sink in.

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Biden made more phone calls and continued thinking about what a campaign would look like. But the worry stuck with him. Clinton’s team was making moves to pressure him to stay out of the race, which he responded to with a shrug and annoyance. Speculation in the press got intense. “I knew it would be an uphill race against Hillary, but I thought I could win,” Biden wrote in his memoir.

On October 20, the day before he ultimately decided not to run, speaking at an event with former Vice President Walter Mondale, he shifted a key element of the story of the May 2011 raid by Navy SEALs who had killed Osama bin Laden: Instead of saying he’d opposed it, as he’d done during the 2012 reelection campaign in remarking on how steely Obama was, he said he’d opposed the raid in a national-security Cabinet meeting, but then followed Obama back to the Oval Office and told him he actually was in favor of it. To many, this seemed like an assertion in preparation for a campaign, especially since Clinton was running on her own national-security credentials and was known to have been a strong backer of the risky but successful mission.

That afternoon and into the evening, after he’d appeared with Mondale, his staff fielded questions about how he’d changed his story on the bin Laden decision. As reporters asked whether that meant he was running, Biden continued talking with people about the campaign.

He wondered whether he was ready. His supporters believed he could win.

“It’s hard to look back now, but that’s what I told him,” says James Smith, a former South Carolina state representative and friend who was on the phone with him that night in October, as Biden sat up late at the Naval Observatory.

Biden said he needed to sleep on it. He went upstairs to the residence and talked with his wife, Jill. The next morning, aides woke up still thinking he might run, but Biden had already called Obama early to say he was out. Announce it in the Rose Garden, Obama immediately offered. He said he’d stand by Biden’s side, calling in all the press to make as big a deal of it as possible. Also, he wanted to lock this in. The Biden speculation had been hanging over the administration, the Clinton campaign, the entire Democratic world, and, according to a former White House aide, once Biden had made his decision, Obama wanted it over and settled as quickly as possible.

A few blocks away from the White House, Tad Devine, Bernie Sanders’s main political consultant, and Jeff Weaver, Sanders’s 2016 campaign manager and now senior adviser to his 2020 campaign, were supposed to be meeting two Washington Post reporters for lunch to convince them to take the senator seriously. The reporters canceled the meeting over the Biden news. Devine and Weaver ended up sitting at the restaurant bar, watching Biden’s speech on TV.