Probably. What's the alternative, voting for deranged neo-Nazi-defending, pedophiliac-justifying, anti-intellectualistic, faux-populist, rage machines in the name of tax cuts on top of our already fairly low taxes? LOL
It seems hard to believe that a permanent vacuum can exist in the center of the political spectrum. At some point (coming almost certainly after Trump leaves office, granted), the currently rabid levels of partisanship will de-escalate and the Republicans will move away from Trumpism and back towards more measured forms of right-wing politics. Whether the Democrats also make a move to the center is less clear. This change in partisan dynamics will make it difficult for Sanders or other members of the progressive wing to maintain strong margins with college-educated whites.
What can possibly give you the idea that Republicans will move away from the alt right?? They just elected Roy Moore as their candidate in Alabama even after Trump told them not to!
You have moderate Reps like Flake, Dent and Lobiondo retiring left and right and everything we see on the table right now shows the fringe becoming more and more powerful as time goes on.
There is a strong 'alt-right' contingent in the Republican party, but it's not the whole. It really depends on who is winning the nominations; it was entirely possible for Trump to have lost the nomination to a more conventional candidate, just as the primaries in VA and AL between 'alt-right' and more conventional candidates were fairly close. It's true the party as a whole is moving in that direction, but there are other factions.
