If Cruz does win with over 50% of the Wisconsin vote, this is nothing less than a complete repudiation of Trump, but it does not mean Cruz gets the nomination.
Two scenarios;
1. Cruz and Trump manage to keep the Romney Rule in place that basically will only allow Trump and Cruz to be put up for nomination for any of the ballots.
I dont see this ending anywhere other than a Trump-Cruz ticket unless Trumps ground game is totally incompetent. Trump will have more delegates so he will have the upper hand, unless Cruz has secretly stealthed a bunch of Trumps people. A Trump-Cruz ticket solves a great many problems, and if they work to stiff arm the Establishment on Rule 40B, they may bury a lot of hatchets and make up.
2. The party Establishment lawyers the thing and gets the Romney Rule removed or dismissed somehow, and it goes into multiple ballots.
This could result in almost anything. The change I have read of most often is that they will limit the nomination to those who have at least one delegate, which opens the door for a whole bunch of people. Here is the list with the delegate count:
- Donald Trump: 737
- Ted Cruz: 505
- Marco Rubio: 171
- John Kasich: 143
- Ben Carson: 9
- Jeb Bush: 4
- Carly Fiorina: 1
- Mike Huckabee: 1
- Rand Paul: 1
My bet is that the Establishment will push for Jeb! again, but they may compromise and go with Kasich and Rubiofor VP, but VP is kind of immaterial here at this point.