Former Secretary of State Hillary Clinton delivers Hunter College’s commencement address, Wednesday, May 29, 2019, in New York. (AP Photo/Mary Altaffer)

If you’ve paid attention to political media the last week, you’ve probably noticed that Hillary Clinton has jumped back into the public spotlight. A new “documentary” (which is really just a fluff piece) showed her absolutely trashing Bernie Sanders late last week.

she's going to hell btw 🤠👍 pic.twitter.com/z1VL42ZPCd

— 🚕 (@bobby) March 7, 2020

Given that, it’s becoming increasingly odd that she won’t just endorse Joe Biden. He’s the establishment choice, he’s leading in all the polls for the nomination, and you’d think he represents exactly what Hillary wants.

But nope, she won’t endorse him.

WATCH: Hillary Clinton refuses to endorse Joe Biden, after saying that Bernie Sanders isn't the "strongest nominee against Donald Trump."

CNN's Fareed Zakaria quickly points out that there isn't anybody left in the Democrat's primary. pic.twitter.com/JgTXJVXTc9

— Francis Brennan (Text TRUMP to 88022) (@FrancisBrennan) March 8, 2020

I’m gonna guess she’s not holding out to endorse Tulsi Gabbard because Hillary hates her guts. That only leaves Biden. So what’s the hold up? Does she know something we don’t?

It’s a fair question and one that leads down a lot of different paths. One theory is that Hillary believes she can swoop in at the convention and take the nomination. This would be based on a scenario where Biden’s mental collapse continues and becomes something Democrats simply can’t ignore. That’s not a bad bet at this point, as he once again “gaffed” today on the stump and it’s become an every speech thing for him. The more he speaks, the worse he looks. If Hillary backs him now and he drops out in the summer, she’ll be one of the “suckers” who didn’t pay attention to the obvious.

I’m skeptical though. It’s pretty far-fetched to think the Democrats would throw up a divisive two-time loser like Hillary instead of say, Elizabeth Warren or Amy Klobuchar, who actually ran campaigns this cycle. If she’s jockeying for the nomination, she’d have done better to just run, right?

So if it’s not some complicated scheme to run for president again in 2020, what it is? My assumption is that she’s really just this egotistical and is skeptical of a Biden candidacy. After getting beat in 2016, she simply doesn’t want to subjugate herself to another Democrat candidate this early, especially one who can’t finish a stump speech without forgetting what he’s doing.

While I believe the latter is the most likely explanation, it is interesting to imagine some of the other reasons she might be doing this. Whatever it is, it’s getting increasingly odd that she won’t just throw her support behind Joe Biden. We’ll find out soon enough what she has cooking.