We’re already seeing some early obituaries for U.S. Senator Kamala Harris’s presidential campaign.

But they’re premature.  Yes, Kamala’s campaign is on the decline. But she has one hard fact going for her.

Joe Biden is 76. He will be 77 before Thanksgiving.

That’s historically old for a leading presidential candidate. And Biden shows his age—he’s mistake-prone enough that he could self-immolate. So age, one way or another, could end his campaign quickly.  (And that might be a good thing for the country—¸there are many reasons to avoid having 78-year-old presidents, which is how Biden would be if he were sworn in in 2021).

Kamala is still best positioned to step into Biden’s spot in the campaign if Biden can’t continue. She could inherit much of his support from two constituencies: more moderate Democrats, and African Americans.

Of course, she could be outmaneuvered for that support. Corey Booker, who is a stronger candidate than he appears in polls, could step into a Biden void as well.

Kamala remains a heartbeat away from being a top-tier presidential candidate. And that’s not nothing, when that heart is about to turn 77.