Barack Obama thinks about his brand and his legacy a lot, and he dreads what Joe Biden might do to it. This month alone, Biden mistook New Hampshire for Vermont even though the sole reason he was in that part of the country was the first-in-the-nation primary, which is famously not held in Vermont. He said RFK was assassinated in the 1970s. He said he couldn’t remember the name of the British prime minister in the midst of bragging about his foreign-policy chops. And he speculated about what it might have been like if Obama had been assassinated.

This last, ghastly gaffe might be too much for Obama to take. Obama believes his brand is cool, technocratic, tightly controlled, a bit wonkish and professorial, inspirational, buttoned-down, Ivy League, definitely forward-looking. Biden is warm, free-wheeling, intellectually ungifted, frank and unguarded to the point of outright sloppiness, so old he served in the Senate alongside segregationist Democrats, and so out of touch he actually touts his friendship with these guys. Obama thought back in 2008 Biden was so old that he would never again run for president, his team strongly discouraged Biden from entering the race in the fall of 2015, and Biden’s jaw-dropping string of verbal blunders indicates a strong possibility of incipient cognitive decline.

As Barack Obama surveys the Democratic contenders for 2020, he must be thinking: 1) None of these people has half my political skills but 2) Elizabeth Warren is my kind of gal. Warren is also cool, wonky, and professorial, also a Harvard product. Though she is 70, she looks younger and hasn’t displayed any signs of cognitive decline. Like Obama, she would be labeled a “historic” president. If she reached the Oval Office, he wouldn’t have to cringe every time she opened her mouth. He wouldn’t have to worry that her back-slapping tendencies would allow her to get rolled by Mitch McConnell. He trusts her so much that he let her guide one of his signature achievements, setting up the Consumer Financial Protection Bureau.

One poll released in late August gave Warren a one-point lead over Biden. Two other polls released in the second half of August show her within three points of Biden. True, most others give him a double-digit lead, and some have her in third place, albeit narrowly, behind Bernie Sanders. Yet she’s close enough that Obama must be wondering if his endorsement could vault her into the lead position.

What then? Like everyone else on earth, Obama notices that Biden looks like a much stronger candidate than Warren in a matchup against Trump. Warren might well be Hillary 2.0: She’s off-putting. She’s smug. She’s . . . a she. Polls show Democrats are extremely worried that the American people won’t accept a woman president. The more she uses words like “My Daddy” and ostentatiously drinks beer, the less relatable she is. It’s hard to imagine the American people are thinking, “Yes, this is the voice I want to listen to every day for the next four years.”

So there would be risk involved in backing Warren. But from Obama’s perspective, there’s also risk involved in Biden’s becoming president and embarrassing him every day. Maybe even, in his dotage, Biden might let what’s left of the Obama legacy slip away. If Obama thinks like most Democrats, he probably believes that nonsensical hullabaloo about email servers, not Hillary Clinton’s deficiencies as a candidate or sexism, was what cost her the presidency.

Obama proved to be a failure at almost everything except getting Obama elected to office, but he is not a man notable for a modest view of his own skills. He must be thinking his star power could restore black turnout to levels approaching where it was when he was on the ballot. He must be thinking that with a push from him, and a little help from his turnout wizards, Elizabeth Warren could avoid Hillary Clinton’s errors and enter the White House.

If Obama were to endorse Warren, the 2020 Democratic primaries would be upended, and Obama would be praised for lighting a path to a genuinely progressive presidency. And if Biden won the nomination anyway, no biggie: Obama could simply campaign for him in the general election and settle for a less-than-ideal Democratic presidency. I’m guessing Obama comes out strong for Warren.