If Pat Toomey of Pennsylvania wins, for instance, it will tell Republicans that their own brand hasn't been hurt too badly by [Donald] Trump's negatives.

If [Donald] Trump loses narrowly, it will make it much harder for the GOP to unify. Under that scenario, the Trumpists are likely to argue that the election was lost because the Republican establishment failed to rally around the choice their own voters made.

The Republican Party, right now, is a conservative populist party.

Senate races have tightened along with the presidential race. Watch to see how many Republican Senate candidates outperform Donald Trump - and how many hang on to their seats in states that he loses.

The GOP establishment, in particular, is facing a pick-your-poison kind of decision. Many establishment Republicans dislike [Ted] Cruz personally. He has no Senate endorsements.

[Donald] Trump has said he will accept the results of the election - if he wins. And he has said the only way he can lose the election is if it's stolen from him. Weeks before any votes were cast, he was predicting widespread voter fraud. So if he loses, what does he do?

There's disgust with what people called a broken political system, and they're really angry at elites, whether it's the Republican establishment or particularly the media who they feel look down on them, tell them they're bigots.