OP - I'm assuming you meant to say Pence immediately becomes President (not Biden). Interesting scenario.... President Pelosi has a nice ring to it, there would be Republican heads exploding all over the place.
I don't think Pelosi would run, but let's say she did, who would run against her?
Perhaps Lindsey Graham could fully transition ala Bruce/Caitlyn and run as the first transgender candidate. What do you think?
Lindsey wouldn't have to change her name and could probably get the surgery at half price since he already has no balls.