It’s so friggin early to be counting on a win for any candidate, including Trump.
We have seen this happen time and time again. All the early sprinters fade....the methodical plodders catchup and pass them by like the turtle and the hare story.
So no, don’t underestimate Cruz or over estimate Trump.
However, this is an unusual election cycle. One can throw all the former methods out the window. They aren’t going to work in 2016.