Evaluating the impact of Republican Party divisions on Trump's candidacy
“As bad as the Republican convention was for Trump, he still managed to get a bounce. This suggests that there is a broad constituency for Trump’s anti-establishment brand of politics, which should not be underestimated.
But the infighting is a major distraction. Normally a candidate seeks endorsements from neutral figures outside of his party. Clinton is doing this successfully but Trump’s energy is wasted on internal rebellion. To be fair, some of these defections on the part of senators in close races reflect their own self-preservation instincts and not necessarily a systemic breakdown of party unity.
A worst-case scenario would be a third party plucking away a prominent former Republican senator or governor as its [presidential] nominee in a bid to steal away disgruntled establishment voters. That would mean open war and a total collapse of party unity.”