The Establishment thinking is that if Trump beats Cruz in Iowa, they can then beat Trump with Rubio, Bush, or Christie.
But that is horse manure and if they were not all incompetent morons they would know it. These guys have not made a dent in Trump’s popularity. The only guys who has is named Ted Cruz, and he has done it by being humorous and kind to Trump.
If Trump beats Cruz in Iowa, the man still does not bleed. That makes him stronger and more and more locks Trump in as a viable contender. It makes it more likely that Cruz’s coalition breaks to Trump and sustains Trump, who can also pick up blue collar voters in northern states and the Rust Belt to sustain his candidacy.
The truth is this: the establishment wing of the Republican Party would rather Hillary Clinton win than Ted Cruz win. If Ted Cruz wins, a good number of the establishment staff would be on the unemployment line, shut out of jobs in the White House that they covet.