If Trump decides to go third party early on...

[Crumpets]

Let's suppose early in the process Trump drops out of the Republican primary and decides to run third party. How does the Republican primary evolve with the knowledge that the person they nominate is almost certainly headed toward defeat and will have to face Trump and Clinton in the general? Do the Republicans put up a moderate to try to win the center? Do Trump voters turn out in the Republican primary anyway and put in someone like Carson or Cruz? I'm just curious because I don't see Trump deciding to run third party so late in the process that he'd have to basically run as a write-in candidate everywhere.

[wolfsblood07]

Bush, because let's face it that's who they're going to nominate anyway.

[Attorney General & PPT Dwarven Dragon]

Bush, because let's face it that's who they're going to nominate anyway.

There is absolutely no enthusiasm for Bush, and the party can't fraud the nomination for him with his like 5% national support. The establishment leaders are already jumping to Rubio's campaign if you didn't notice.

[publicunofficial]

Trump's supporters would ignore the Republican primary altogether, rather than flock to Cruz or Carson. My guess is Rubio.

[Adam Griffin]

Most of the Republican Party's primary voters - no matter how far off the deep end they've went as of late - are going to abandon their long-established behavioral tendencies of "falling in line". As such, they'll still participate in the Republican primary and they will flock to Ben Carson, who wins literally every head-to-head match-up against fellow GOPers as of now (NYT did a Condorcet poll on this; lost the link but it's a good read).

[Fuzzy Bear]

I see the final outcome as a 396-142 electoral landslide for the Democrats.  I also see the Democratic candidate failing to reach 50%, and struggling to make 45% in such a race. 

I also see a Trump vote as a Republican vote.  Republicans will run stronger for Senate races if Trump is a 3rd party candidate, since Trump's supporters (like Perot's in 1992 and 1996) are likely to vote Republican for their Reps and Senators.  A Trump 3rd party bid actually strengthens the GOP's likelihood of keeping the Senate.