Ted Cruz’s failure to endorse rival Donald Trump for president at last week’s Republican National Convention in Cleveland, Ohio has apparently caused his favorability rating among GOP voters to collapse, according to a national survey and an Ohio poll. An NBC News/Survey Monkey nationwide poll released Tuesday and a PPP survey of Ohio Republicans released Monday confirms the shocking collapse in Cruz’ favorability rating among Republican voters following the convention seen in a CNN/ORC poll released Monday. CNN/ORC: “Cruz’s move, however, appears to have backfired. While 60% of Republican voters had a positive impression of the former presidential candidate before...