Jeb Bush, trailing badly in polls here and itching to get to New Hampshire, used his farewell Iowa campaign event to ask caucus-goers to do what he couldn't: Stop Donald Trump. "You have a chance to define the next stage of this race," Bush told a ballroom full of supporters in an Embassy Suites hotel on Monday afternoon. "I'm counting on you and I trust you." The former Florida governor has essentially conceded Iowa, where polls show him in the low single digits. Bush will not be holding a caucus night party, instead leaving the state this afternoon for New...