Andrew Malcolm, the insightful McClatchy columnist, lays out the scenario with a fairly high probability of unfolding. Read the whole thing, but here is the gist:

After Ted Kennedy’s primary challenge pretty much doomed Jimmy Carter’s 1980 re-election, Democrats created so-called superdelegates. They are hundreds of party elites appointed as convention delegates to ensure that a crazed nobody can’t seize the nomination and doom the party’s general election efforts.

Clinton did not need them in 2016; she won the nomination outright. But the meme survives that superdelegates rigged the voting against second-place Sanders.

To address that smoldering resentment, this time the Democratic Party has forbidden the unelected superdelegates from voting on the convention’s first ballot. But be careful what you wish for, folks.

Republicans pick their convention delegates through winner-take-all primaries and caucuses, enabling a strong performer — say, an incumbent president lacking a viable challenger — to sew up the nomination early. This saves money while providing more time for healing, fundraising, unifying and defining the opposition.

Not Democrats. They do it piecemeal. With a minimum 15 percent of the votes, candidates get their proportionate share of delegates. Thus, in the 2016 Iowa caucuses, Clinton edged Sanders by one-quarter of 1 percentage point, so Bernie got 21 delegates to her 23.

In New Hampshire, just next door to Sanders’ Vermont, he blew Clinton out of the water vote-wise, but she still took away nine delegates to his 15.

This everyone-gets-a-trophy-approach strikes Democrats as nice and fair. In a crowded field, however, it also prolongs the divisive arguing and postpones the clinching day, quite possibly creating a contested mid-July convention in Milwaukee.

If no one gets a majority of the 3,768 regular delegates on the first ballot there, here come the 765 unelected superdelegates to impose on the field their binding choice of a candidate they believe most likely to oust Trump.

If Sanders has the most delegates by then, they can endorse the occasional Democrat and pray that Americans will fall for the first democratic socialist and oldest commander-in-chief in U.S. history over a mercurial billionaire with a big mouth.

Or this establishment cabal can choose someone else more politically palatable for a general election and confirm the powerful left’s suspicions and fears of rejection through another rigged convention. Which leaves precious little time for healing.