Marco Rubio’s campaign says supporters of the Florida senator should back John Kasich in Ohio on Tuesday if they want to stop Donald Trump. “If you are a Republican primary voter in Ohio and you want to defeat Donald Trump, your best chance in Ohio is John Kasich,” Alex Conant, Rubio’s communications director, told CNN. “The same is true here in Florida,” Conant said, emphasizing that Rubio is the candidate best positioned to beat the real-estate mogul in the state’s primary Tuesday for its 99 winner-take-all delegates. “Yes, my answer is John Kasich is the one candidate in Ohio that...