After 8 years, Trump would probably be unpopular (approval in the low 40s.)
I think ambitious GOP pols like DeSantis, Hawley would prefer to sit out until 2028 in this scenario. Pence is the GOP nominee.
After blowing both the 2016 and 2020 elections, the "establishment wing" of the DPUSA would be pretty shot. They nominate Elizabeth Warren.
Warren vs Pence ends up being closer than expected, but Warren wins 286-252.
Probably low 30s. Trump does better on foreign policy but inflation and high interest rates were coming regardless of President. Dobbs would still have happened, and Trump would get the full blame for it since it would happen under his watch.
Trump is such a polarizing figure that he bottoms out in the low 40s. He would keep the base, although as a lame duck he could expect some further bleeding. Maybe that's enough to give him some polls in the mid 30s, but definitely no lower than that.