It was undeniably a good night for Cruz, who earned more delegates than Trump. Trump did, however, narrowly edge Cruz out on the actual number of votes received today:
Trump -- 230,443
Cruz -- 230,209
Rubio -- 85,064
Kasich -- 62,554
Little Marco was the big loser. He wasn't merely uncompetitive in all four states, he couldn't even manage second anywhere and finished last in Maine. Florida should be in the bag for Trump. If it's not, a brokered convention becomes probable. The markets now have Kasich's chances at the nomination better than Rubio's.
Trump continues to perform below polling projections nearly everywhere. Ohio could be slipping out of Trump's grasp, and he may be in trouble in Michigan, too. Kasich could conceivably win both of them.
The good news for Trumpians is that it's Cruz rather than Rubio or Kasich firmly ensconced in second place. A lot of the theocratic states have come and gone. The more secular contests (and the remaining heavily Scots-Irish religious states where Trump has bested him so far) will be tougher for Cruz, even if he continues to outperform his polling numbers.
Trump and Cruz have both hinted that they will not accept a brokered outcome that cuts the winner (ie whoever has garnered the plurality of votes) out of the nomination. It's looking like between the two of them, with winner-take-all states fast becoming the norm, they'll control upwards of four-fifths of the assigned delegates when the primary season wraps up.
A Trump-Cruz ticket may not yet be totally out of the question, improbable as that seems based on their (public) mutual hostility for one another. If they go into the convention understanding they're both about to be cut out, they might strike a deal and announce it before the palace eunuchs are able to put their backroom scheming into action.