NEW YORK --WithTed Cruz winning the Wisconsin Republican presidential primary Tuesday night, what happens next for rival Donald Trump? Does the Cruz victory give the "Stop Trump" movement momentum, or will it be crushed in New York -- Trump's home state and the next to vote?

CBS News political director John Dickerson, host of "Face The Nation," told "CBS Evening News" anchor Scott Pelley the Wisconsin win is huge for Cruz.

"We still don't know how the delegates are going to get apportioned, and that's important," Dickerson pointed out Tuesday night, before the results were known for each congressional district. "If Cruz gets all 42, that's a slam dunk win -- that's all the delegates in the state and it's a possibility."

Dickerson said both Cruz's and Trump's campaigns will attempt to explain the results.

"We're going to see this battle between Cruz and Trump to argue why it happened," Dickerson said. "Was it the idiosyncrasies of Wisconsin, or was it Donald Trump's bad last week? Was it the fact that conservatives decided finally that he's not really one of them? Whoever wins that argument, whoever defines what Wisconsin means, will then be able to fight it out over the next couple of weeks."

The exit polls offered some clues, according to Dickerson.

"If you look at those who made up their mind in the last few days, he (Trump) got 35 percent of the vote, Cruz got in the low 40s," Dickerson said. "That's not as big a margin as Cruz has in the overall vote. Given how bad the last week was for Donald Trump, you could imagine a real fall off the table, but in those who made their mind up in the last week, he didn't do very well at all, and Cruz had a much bigger margin in that group. So it's hard to figure out exactly what it might mean for him."

To see the rest of what Dickerson had to say about Wisconsin and the campaign trail to come, what the video above.