Greg Sargent in the Washington Post described how Donald Trump, in spite, might bring down the Republican Party (or leave it substantially weaker).
I can't see the downside of that outcome.
Bloodbath alert: Donald Trump issues new threat to destroy the GOP
"Rather, what really matters here is that Trump is signaling his possible intention to do maximum damage to the party if he is denied the nomination, through whatever means he has at his disposal.
We simply don’t have any idea yet how much damage Trump can do to the Republican Party. It could go well beyond denying Republicans the White House. If a raging Trump, having lost the nomination at a contested convention, urges millions of his followers not to vote Republican, it could cause large numbers of GOP voters to sit out the election, potentially rupturing their plans for holding their Senate majority."
Anything that puts Mitch McConnell out of the Senate majority leadership job is good in my book.