What to know about the Republican National Convention in Cleveland, which is in its third day:
• The party's deep fractures were on display Wednesday tonight: Among other incidents, Ted Cruz told delegates to "vote your conscience" and Scott Walker barely mentioned Trump's name.
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Republicans hold a mere 52-48 Senate majority while outnumbering Democrats in the House by 44 seats, with five vacancies.
But elections are not about mathematics, or determined by probability.