Cruz will probably be the nominee by literally stealing delegates the same as Paul did in 2012, but on a much larger and more sanctioned scale. These state conventions are going to be hilarious to watch. If the fighting was bad last time, this time it's going to be insane.
Not exactly the same. Paul was trying to steal pledged delegates to vote for Paul on the first ballot. Cruz is infiltrating Trump's pledged delegates but they can't vote for Cruz until the second ballot. So if Trump wins enough pledged delegates all of this stuff will be a moot point.
Cruz is also going after unbound delegates. In theory Cruz could use them to win on a first ballot but he would have to really close the gap with Trump by the convention and go in with close to 1100+.
But going after the unbound is also a defensive move to keep them from Trump. If Trump doesn't get 1237 he is going to be very close. Cruz' ninjas will mean that Trump is going to lose delegates on the second round, so Trump really needs to win on the first round. The unbound delegates are the way he can win with less than 1237. Say Trump goes in with 1200, then he just needs 37 of these unbound and he is the nominee. And you can be sure that Trump will be handing out jobs, ambassadorships, free travel to the convention and possibly even suitcases of money to make that happen.