Republican elites are begrudgingly embracing Ted Cruz—and hanging Marco Rubio out to dry. Panicked at Donald Trump's dominance and dismayed by Rubio's continued inability to do anything about it, some top Republican power brokers are turning to Cruz, putting aside their policy and personal misgivings to back the candidate they now openly label as their best hope to stop Trump's GOP takeover. "He seems to be the only guy who's got some momentum, and is probably the best situated if there is anybody out there to beat Trump," said Austin Barbour, a prominent Mississippi-based GOP operative. "That's why there are...