This seems to suggest that Cruz can definitely be competitive against Clinton and that he wouldn't lose McCain style like some people think. Rubio seems to be the most electable candidate as a lot of people like him and moderates don't think he's too radical for them. Cruz probably draws a good contrast from Clinton who voters can't stand. I'm surprised Trump is doing this well and I doubt Trump would have the smallest gender gap, considering his lack of appeal to women. This poll might be generous for Trump.
This is a poll 11 months out from the election... It doesn't suggest anything.