now that christie and fiorina are both out, expect to see bush jump by 5-10 points across the polling spectrum.
once that stabilizes a little, expect to see moderate republicans move from trump to bush due to the tea party no longer being seen as an existential threat to the party.
you have to understand that this is the major reason that trump is polling well: he's not a tea party candidate. and, thus, when compared to the hard right candidates like rubio and cruz, trump comes across as a moderate.
that's why trump is hitting bush rather than cruz. he knows who the serious candidate is.
the two serious candidates right now are bush and kasich, and it doesn't seem like kasich has much of a chance right now south of the mason-dixon line.
if big money has it's way, it's going to pick cruz. he's the insider guy. but, the voters don't actually want that kind of social darwinism.
what bush needed was for the field to narrow. and, if he can find a way to force kasich to drop, then he's a walk to the finish line.