Final thought: Groundhog Day in March as February's patterns carry over
In the early primaries and caucuses on the GOP side, a few patterns became clear. Donald Trump marched toward the nomination by winning most groups of Republican primary voters, but Haley proved a bit more competitive in pockets with large numbers of college-educated voters. Trump has expanded his 2016 coalition by winning more voters on the right, which we can see by his strength in places where Ted Cruz did well eight years ago. Haley, meanwhile, competes among moderates. Tonight, that meant dominant wins for Trump across a set of states, from Virginia and North Carolina to Texas and California. Among tonight's states, Virginia's demographics make it more friendly to non-Trump candidates — Rubio almost won it in 2016 — so Haley's failure to breech 40 percent there is yet another sign that she's able to win only a minority faction within today's GOP.
Overall, there isn't much surprise in tonight's Republican presidential results, beyond the question of whether Haley will eke across the 50 percent threshold and so take home all of Vermont's delegates. In part, that reflects the nationalization of presidential politics. In state after state, the same kinds of communities lean towards or away from Trump, so the results follow pretty consistently from a state's demographics and prior voting behavior. That makes for predictable patterns — and a less than surprising Super Tuesday.
—Dan Hopkins, 538 contributor