Joe Biden drove Democrats toward the emotional brink on Tuesday, as he was greeted with cheers by hundreds of firefighters during a conference in Washington, D.C. “I appreciate the energy you showed when I got up here,” he told the crowd. “Save it a little longer, I may need it in a few weeks. Be careful what you wish for.” He continued to tantalize them after the speech, telling MSNBC’s Andrea Mitchell that he would make an announcement about running in 2020 in “just a little bit,” confirming his place in the political firmament as the most maddeningly indecisive presidential candidate in modern history. Or merely the most coy: according to a House Democratic lawmaker who spoke to The Hill, Biden is absolutely running in 2020. (“I’m giving it a shot,” Biden reportedly told this congressperson during a phone call within the past week.)

A spokesperson for the former vice president told The Hill that Biden “has not made a final decision.” But it’s hard to imagine that he isn’t eminently close. Billionaire Michael Bloomberg, who might have challenged Biden for the party’s centrist vote, is out of the running. Ditto Ohio Senator Sherrod Brown. Most of the rest of the 2020 candidates are scrambling to the left. Which leaves only Beto O’Rourke in the top tier of white, male, centrist-friendly candidates who are being hyped for their ability to connect with disaffected Republican voters.

In his same conversation with Mitchell on Tuesday, Biden said that O’Rourke is a “good guy.” Yet Biden and Beto, if both decide to run, are headed for a potentially messy collision. While both have adopted several progressive positions, their hesitance to go full-bore Bernie Sanders has alienated some corners of the party’s activist wing. Some have hailed O’Rourke as a “white Obama,” for his sunny disposition and effortless charisma, but lefties grappling with the uglier side of Barack Obama’s legacy are turned off by the comparison. (Rep. Ilhan Omar wasn’t speaking just for herself when she called Obama a “pretty face” who “got away with murder” in the Middle East.) Biden, of course, is also defined by his easy charm and association with the former president. Those qualities could be a plus for either man, but will almost certainly put them into a heads-up competition for the same electoral lane.

Biden, who is currently leading most polls by substantial margins, appears to be taking a longer time getting to “yes” than Beto, who appears poised to jump in any minute. But at this stage of the race, polling is as much a reflection of name recognition as voter approval. According to a new Monmouth poll, Biden and Beto are disliked by a similar share of voters—it’s just Biden’s favorable numbers that are so much higher. For now, Biden has a net favorable rating of 63, while O’Rourke sits at 26.

In theory, whoever comes out on top might pose the most significant threat to Donald Trump, as several G.O.P. strategists recently told Vanity Fair contributor David M. Drucker. So far, their strategies to get there essentially boil down to a generational difference. The septuagenarian Biden has more than four decades of political relationships built across several swing states, as well as the cult status of a beloved elder statesman with ties to the Obama administration. The 46-year-old O’Rourke boasts a massive fund-raising machine, digital savvy, the ability to turn formerly red states into swing territories (see: Texas), and the sort of fresh, pop-culture-phenom status formerly held by Obama himself. Even as they prepare to go head to head, both 2020 contenders will need to keep an eye on the left, where early polls show Sanders neck and neck with Biden.

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