Bernie Sanders is correct both that the 2016 Democratic presidential nomination was rigged against him and that the chief culprit is Democratic National Committee Chairwoman Debbie Wasserman Schultz.

It goes far beyond the super delegate party regulars who support her almost unanimously and now make up most of her delegate lead. It goes beyond the near-riot at the Nevada state Democratic convention or even the closed nominating contests that favored Clinton even when the voters didn't.

Party chairs are supposed to remain neutral in presidential races, but Wasserman Schultz, who served as co-chair of Hillary Clinton's campaign in 2008, has not been neutral at all.

She sharply limited the number of debates and scheduled them for times when few were likely to watch, such as Saturday nights, to limit Clinton's exposure to attacks and deny her opponents name recognition. She entered into a joint fundraising agreement with the Clinton campaign in August 2015, then shut off Sanders' access to the party voter database last December, with the first primaries and caucuses just a few weeks out.

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If Republicans tried to do these sort of favors for their establishment candidate, former Gov. Jeb Bush, Republicans would clean house at the national committee, and party chairman Reince Priebus would be looking for a job.

And here's the best part, as far as Republicans are concerned: It's going to hurt the Democrats, and badly.

Sanders has won four of the last five Democratic primaries and is poised to win more in the final big day of primaries on June 7. He's not dropping out, even if Clinton clinches the nomination as expected. He wants to go to Philadelphia, accept the nomination if Clinton is indicted or otherwise can't claim the mantle, and push for progressive planks in the Democratic platform. He has suggested things could get interesting.

Asked if the convention could get rough, Sanders said: "So what? Democracy is messy. Everyday my life is messy. But if you want everything to be quiet and orderly and allow, you know, just things to proceed without vigorous debate … that is not what democracy is about."

Meanwhile, Clinton's double-digit lead over Trump has been erased. Some polls even have the mogul ahead. Clinton is not a great campaigner. Republicans have begun to line up behind Trump. And Trump and Sanders have come to have something in common that poses a serious threat to Clinton – both poll well among independents.

Thus, one recent poll said only two-thirds of Sanders' primary supporters planned to vote for Clinton if she is the nominee. In fact, one in six in most polls, but up to 20 percent in others, say they would vote for Trump rather than Clinton.

In short, the winner of the Bernie Sanders-Clinton/Wasserman Schultz/Democratic machine spat is Donald Trump. The Democrats can't unite. Their candidate is uninspiring on the stump. The apparent loser of the primaries has all the momentum. And those disaffected over how he has been treated might well bolt for the Donald.