What kind of loser will Bernie Sanders be? He's got three choices
During his barnstorming rallies to massive audiences, Bernie Sanders is fond of declaring "enough is enough!" And after the latest round of primary results, many Democratic party leaders will be hoping Sanders now feels similarly about his own campaign.
Sanders and his team should take immense pride in what they've achieved over the past 12 months. On July 8 2015, the RealClearPolitics polling average had the Vermont Senator on a mere 14.3%, almost a full 50 points behind the apparently bulletproof Clinton. To the extent he was noticed at all, Sanders was treated by the press and Clinton supporters as a benign but crusty uncle, well-meaning but toothless.
One year on, Sanders has emerged victorious in more than 20 states, and at one point in April he reduced the gap in that same average to just 1%. And those victories are just half the story.
Most importantly, Sanders and his followers have played a role in forcing Clinton to embrace her own progressive instincts rather than taking to the safety of the centre ground. He has also ensured that "socialism" is no longer a taboo word in American politics, at least not in a Democratic primary. Meanwhile, Winnie Wong, the digital strategist behind #FeelTheBern, will probably never want for work again.
Despite all these achievements, Bernie has fallen short. So what should he do now? If we look to the recent past, there are a few well-trodden routes he can take.
Path #1: unity at all costs
Sanders doesn't have to set his own example of how to unify the Democratic party after a divisive and close primary campaign. Eight years ago, Hillary Clinton herself showed everyone how it's done.
After an equivocal statement on the night of the last primaries, Clinton formally dropped out four days later and gave Obama a full-throated endorsement. Later that month, in a symbolic gesture, the two former rivals made a joint appearance in the aptly-named New Hampshire town of Unity, where they had both captured 107 votes in the state's primary.
And to cap it all, it was she who stopped the (well-choreographed) roll-call of delegate votes at the Democratic convention to formally seal Obama's nomination. She then used her convention speech to declare: "Barack Obama is my candidate, and he must be our president."
Despite the lingering bitterness of a rancorous nomination battle, her friendship with Republican nominee John McCain, and the encouragement of hardcore supporters (rallying under the slogan Party Unity My Ass), she then hit the trail and worked hard to help secure Barack Obama's victory.
But this year, things are rather different. For one thing, Clinton was a natural potential successor for Obama; to have a shot, she was always going to need his supporters and the goodwill of the party. At 74, it seems unlikely that Sanders will entertain similar ambitions. And while Clinton and Obama endured a fiercer battle in 2008, their policy positions and visions of how politics should be were far closer than Clinton's and Sanders's are today.
Path 2: Berning down the house
Another option for Sanders is to act as a disruptive force and weaken Hillary Clinton ahead of the general election, as Senator Ted Kennedy did to President Jimmy Carter in 1980.
John F Kennedy's younger brother had already shown he cared little for party unity by challenging a sitting Democratic president, and he continued to show contempt for the principle even after Carter won enough delegates to secure the nomination.
Indeed, Kennedy spent the time between the final primary in June and the August convention trying capitalise on Carter's increasing unpopularity in the country. His aim was to enact a rules change at the convention that would allow Carter delegates to jump ship, thinking he could save the Democratic ticket from certain failure with Carter at the helm.
Kennedy ultimately secured neither his rule change nor the nomination, but his staunchly liberal campaign still managed to reverse much of Carter's policy platform. Most conspicuously, the senator gave one of the most memorable speeches of any recent convention, ending with what became his signature line: "The dream will never die."
Rubbing salt in the wound, Kennedy then refused to hold Carter's arms aloft in victory, making the deep rift in the party all too clear.
There are those speculating that Sanders will choose this path to the Philadelphia convention this July, but even given the intransigence of many core Sanders supporters, the rationale for the candidate himself is hard to see.
The Vermont Senator has made it clear that he wants no part in helping to elect Donald Trump in November. A futile act of political arson would achieve the opposite - and it would close off another more appealing path.
Path 3: viva la revolución!
Perhaps the best parallel for Sanders is the Reverend Jesse Jackson, who ran two trailblazing campaigns for the Democratic nomination in 1984 and 1988. Sanders, mayor of Burlington at the time, was one of the few white politicians to endorse Jackson's 1988 run - and like Sanders today, Jackson was hardly beloved by the Democratic establishment, but on his second attempt he finished a surprisingly strong second place to the eventual nominee.
The culturally and racially diverse "rainbow coalition" that Jackson formed in 1984 helped propel Democrats to victories in the 1986 midterms, and his strong performance in 1988 suggested that the power of the coalition was only growing.
While Jackson hoped to become the first African-American to run on a national ticket, Dukakis refused. He nonetheless enjoyed a primetime speaking slot at the convention, and his campaign secured changes to primary rules that made the voting process fairer and more proportional. These changes are now credited by some with opening the door to Obama's victory a generation later.
While Dukakis ultimately met a crushing defeat at the hands of George H W Bush, Jackson kept the rainbow coalition alive, working tirelessly to bring young and minority voters into the party.
Certainly, the Democrats will hope that Sanders plays a similar role in keeping his millions of young voters involved in politics - particularly during the midterm years that have so confounded Democrats over the past decade.
As did Jackson, he will undoubtedly have some concessions to bargain for. We may well be about to see the end of "superdelegates", the hundreds of party grandees who get to cast convention votes for the nominee. And we may soon see the back of the party chair, Debbie Wasserman-Schultz, with whom the Sanders campaign's relationship has all but broken down.
While the Sanders camp has continued to insist he will fight for the nomination all the way to the convention, this will probably turn out to be at most a negotiating ploy. Over the past year, he has captured lighting in a bottle; rather than steal Clinton's thunder, he'll probably use it to electrify the Democratic convention, secure himself a lasting legacy, and fire up his troops for the fight against Donald Trump.
Joe Ryan-Hume also contributed to this article.