I posted this to Facebook a few hours ago:
"Non-partisan (and a bit lengthy) thoughts on the post-Indiana state
of the 2016 US presidential election: The surrenders of Cruz and Kasich
ensure that Donald Trump is the Republican nominee. The party
establishment was unwise to dismiss him as a joke and laugh him off -
Trump has been successful at keeping himself relevant for years, so
underestimating him was a bizarre mistake.
On the Democratic
side, the establishment there has been making the same mistake of
underestimating Bernie Sanders. An insurgent candidate pulling off
surprise wins at this point in the race is, to my knowledge,
unprecedented. Insulting/dismissing him and his supporters would be as
unwise as underestimating Trump so far has been.
This is a fascinating election; Obama-Romney 2012 is increasingly looking like a sleep-a-thon by comparison."
When Donald Trump announced his campaign last year, I didn't think he was running as a joke - I thought he should be taken seriously and I was right. The Republicans who are despairing at him having defeated all of his opponents so far ought to have done more to stop him, if they were that concerned.
As for the Democrats, Bernie Sanders continues to poll well and rack up wins; in fact, many of the upcoming states are favorable to him - perhaps more so now that Trump essentially has the Republican nomination, as some people who voted Trump to keep out Ted Cruz might switch to support Sanders in primaries. Regardless, it is a mistake for anyone on the Democratic side to discredit Sanders and his supporters; if he doesn't win the nomination, it won't be helpful for the Democrats for his voters to keep out of the presidential race.