Net favorable scores:
Cruz 45%
Trump 24%
Yes, Cruz is at the top of favorable board.
http://www.gallup.com/poll/188069/jeb-bush-image-among-republicans-deteriorates.aspx?g_source=Election%202016&g_medium=newsfeed&g_campaign=tiles
What is most interesting, to me, anyway, is the net-favorable percentages coming from Gallup. Trump is -27 among the gen pop. That is the largest number by far. Bush holds a -14.
The rest, Dem and Rep alike, are clustered in the single digits with + or - favorable percentages.
http://www.gallup.com/poll/187607/donald-trump-known-not-liked.aspx