The Biden campaign won’t comment on his potential running mates. But after word leaked that Rice is being vetted, buzz about the possibility has grown, spawning columns with titles like “The Case for Susan Rice.”

The chatter is loud enough that allies of others being eyed for the vice presidency are increasingly worried about Rice, especially because of her close ties to Biden, who, as Obama’s No. 2, had an office just steps away from hers.

Privately, some in California Sen. Kamala Harris’ world have indicated that Rice could be Harris’ most formidable rival for the vice presidential slot. Harris is widely considered the candidate with the best shot at being Biden’s running mate — she went through the press wringer when she ran against him in the primary and has decent name recognition. Like Rice, she would represent the first Black woman on a major-party presidential ticket.

No one rules it out, but there’s less speculation that Rice would run for the Oval Office the way Harris almost certainly would post-Biden. That might give Rice an edge in the veepstakes, especially if Biden — who has hinted he may serve one term — doesn’t want to deal with the distraction of a governing partner eyeing his job.