Trump also will have a bit of bad luck over the next three weeks, because so many of the contests during that time will be in southern states where Ted Cruz has appeal. Marco Rubio also stands to inherit many of Jeb Bush’s financial backers and the lion’s share of his voters, giving him staying power by consolidating “establishment” voters.

Sources close to Trump say that as the front-runner, he stands to clean up in states with winner-take-all rules. That will propel him to the nomination, they believe. But not a single state is winner-take-all until Florida (99 delegates) and Ohio (66 delegates) vote on March 15. With Jeb Bush’s dropping out, Marco Rubio probably has an advantage over Trump in his home state, as does John Kasich in Ohio. Kasich is likely to stay in the race in hopes he can use his delegates to become a power broker at the GOP convention in Cleveland in July. After Florida and Ohio, there are only seven other states that are winner-take-all, making it all the harder for an early nominee to emerge before the convention.

The race goes on from Florida and Ohio. New York will allocate 95 delegates by congressional district on April 19, at which point 68 percent of the delegates will have been awarded. That’s the traditional point at which the GOP nomination race has concluded in the past, but this year it is very likely to go on. The primaries end on June 7, when California will use a congressional-district allocation method to divvy up 172 delegates.