Mitt Romney got 59 percent of the white vote in 2012, considered by many to be a high-water mark with this demographic group. Can [Donald] Trump win a higher share of white voters than Romney and get more of them to turn out?

Republican voters are coalescing behind [Donald] Trump, but many Republican elected officials still say they can't support him.

The winner's margin of victory also matters. If it's a squeaker, that will make the lessons learned for both parties much murkier.

Mitt Romney got 59 percent of the white vote in 2012, considered by many to be a high-water mark with this demographic group. Can [Donald] Trump win a higher share of white voters than Romney and get more of them to turn out?

You have [Donald] Trump and [Ted] Cruz battling it out, and the moderate establishment candidates like Chris Christie or Jeb Bush, Marco Rubio, John Kasich - they have formed a circular firing squad.

[Donald] Trump's path to victory depends on getting historic levels of support from white voters, and particularly large numbers of white, non-college-educated voters.

If [Hillary] Clinton can't boost African-American turnout, even with all that help, the question becomes whether she can make up for it with historic levels of support from Hispanics and suburban women.