Jeb Bush's endorsement of Texas Sen. Ted Cruz Wednesday morning signaled a growing inclination in the oft-touted Republican establishment: that even Cruz would be better for the party than Donald Trump. Leaders in the GOP have long and openly mused that neither of the primary frontrunners fits the bill of an ideal Republican presidential candidate, but the race has failed to yield any alternatives. "It's a signal that there's only a plan A and a plan B," said Mark Jones, a political scientist at Rice University's Baker Institute. "There is no plan C."