While support thus far doesn't necessarily mean anything for the general election, you might be right. But the question is....are the people who support Bush or Rubio right now willing to vote for a Trump/Cruz/Carson if they'd end up winning? Or would they end up staying home or switching sides? And then you have the question of swing voters who might vote R if it's a moderate R but would never vote for T/C/C.Yes, in fact only one establishment candidate has been able to break single digit support thus far and that is Rubio and even his support is waning.
I agree that Kasich and Christie have no shot and should just drop out. It's hard to see how Bush is still viable but I'd trust his chances to rise more than the others.The two that will be duking it out for the nomination from my estimation will be Trump & Cruz. The notion that Jeb Bush, Kasich, or Christy are even in the game is a joke, they are all but done by the numbers but, Bush has a lot of money behind him so he will try to stay in till the convention but, I don't see him ever breaking 10% support, he is unelectable, nobody will get behind him except party elites.