There isn’t anyone on the republican side to really oppose Trump. The typical republican insider is no longer popular with voters, many tried to imitate Trump, but that fails because it’s more about the outsider status than absurd statements. They could have tried an actual conservative candidate, but that’s unthinkable to the republican elite, like running Sanders is to democrats.

The democrats have done a horrible job curating future candidates. The Republicans aren’t much better, but at least have a lot of governors. With 12/16 years of the presidency they have no one electable on the national stage. This is a failure of leadership to not have one cabinet or congressional official be someone with a future.

This leads us to a race where the most popular option would be neither of these two.