On the surface, Martinez is probably the best candidate the GOP could run against Clinton because she takes the novelty of Clinton's bid and raises it to another level. Martinez could wipe out most of Hillary's 70/30 advantage with women, but the biggest risk for Martinez is that the rural ConservaDems could come out even more strongly for Hillary. I still think Hillary would win, but this would be narrowly decided:
299/239 Clinton
Martinez gets the SW back but can't close the deal in the East. Nelson isn't quite enough to stop Martinez in FL.