Bernie Sanders vowed to continue the Democratic primary past the last primary race in June, forecasting a much longer battle with Hillary Clinton than her allies had hoped.
"[Clinton] will need superdelegates to take her over the top at the convention in Philadelphia," Sanders said at the National Press Club in Washington, DC, on Sunday. "In other words, it will be a contested convention."
Down by huge margins among the delegates chosen by voters, Sanders had already opened the door for the party's unelected superdelegates to throw him the nomination. At the press conference, Sanders emphasized one part of this pitch: that the superdelegates in states he's won should swing their support behind his campaign.
"Those superdelegates in states where either candidate has won a landslide victory ought to seriously reflect on whether they should cast their superdelegate vote in line with the wishes of the people in their states," Sanders said.
This superdelegate strategy sounds reasonable, but it's got at least one major flaw: it wouldn't actually win Bernie the nomination.
As NPR's Tamara Keith points out, Clinton would still be ahead in the overall delegate count even if the superdelegates from the states Sanders won shifted to his side.
"If you mandate that the superdelegates be divvied up proportionally, the margin for Clinton narrows further," says the Washington Post's Philip Bump. "But, in the same way that she still has a lead in pledged delegates because of proportional distribution, she has a lead with superdelegates, too."
Why is Bernie Sanders lobbying superdelegates to save his campaign?
So if flipping the superdelegates in states he's won wouldn't give him the nomination, why is Sanders lobbying them?
There are a few different plausible explanations for what might be going on here, according to Matt Grossmann, a political scientist at the University of Michigan.
One is that Sanders genuinely thinks he's the best hope for the Democratic Party, and that he believes that the superdelegates really can be persuaded to rescue his candidacy.
Given how long the veteran senator has been around DC, however, it's almost hard to believe that Sanders himself thinks the superdelegates can save him. The superdelegates are made up of establishment Democratic officials who have been overwhelmingly loyal to Clinton since before the campaign began.
But there's another possible explanation for Sanders's superdelegate strategy — one that doesn't depend on him banking on a scenario that essentially nobody thinks has a chance of succeeding.
The superdelegates are not elected to their roles for the Democratic National Convention, but they do frequently hold elected office — as mayors, governors, and other key positions in the Democratic Party.
Some of these officials' constituents are vocal, passionate Sanders supporters who are not happy to see their local representatives support Clinton.
One Sanders supporter, for instance,started a "Superdelegate List," posting the names and phone numbers of superdelegates for targeted lobbying. More than 3,000 people in Vermont have signed a petition criticizing four of the state's superdelegates — including a sitting governor and senator — for endorsing Clinton despite their state's overwhelming support for Sanders.
By calling for pressure on superdelegates in regions he won, Bernie can demonstrate the power and extent of his vision for the party.
Another possible benefit of this plan: Even if they don't get Sanders the nomination, having more delegates in his corner will make him look stronger for the Democratic convention in Philadelphia this July. That could help his efforts to push for the party to include his policy positions in its official platform, which is approved at the convention.
Of the 712 superdelegates, 520 are siding with Clinton while just 39 have said they'll back Sanders, according to Bloomberg News.
"The more they get that number down, that could potentially help him at the convention change the rule or change the planks," Grossmann says. "The closer he is, the better off he is — that's the line of argument he's making for superdelegates. It's not so he has those people; it's just so the outcome appears closer than it does now."
If Sanders's goal is to push the party to incorporate his priorities, a sustained lobbying drive on superdelegates may be one way to do it. Or maybe he's thinks he's so obviously the right choice for the nomination that others can be convinced, too.