PHOTO: Hillary Clinton and Bernie Sanders debate in Michigan, March 6, 2016

Bernie Sanders seemed almost surprised as he held an impromptu press conference in Florida on Tuesday night. The Vermont Senator had just pulled off the biggest primary upset since 1984. He had overcome a poll deficits of more than 20% in Michigan to narrowly defeat Hillary Clinton, checking her procession to the Democratic nomination for the US Presidency.

After taking in the magnitude of the win, he proclaimed, “What tonight means is that the Bernie Sanders campaign, the people’s revolution that we are talking about, is strong in every part of the country, and frankly we believe that our strongest areas are yet to happen.”

As he noted on Tuesday, Sanders has already “repudiated the pundits” who said he had no chance, with his forthright ideas on the economy and social issues, against the Clinton machine and the mass of Democratic Party endorsements behind her.

But can the feel-good moment last all the way to the Democratic Convention in late July and even beyond?

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The cold reality check is that, to continue his unexpected challenge to Clinton, Sanders will need to top last Tuesday again and again. He will have to achieve even bigger upsets in Illinois, Ohio, and Missouri on March 15 and probably triumph in North Carolina. Then it is on to Wisconsin on April 5 and — with New York on April 19 probably beyond even the biggest dreams of Sanders supporters — Pennsylvania on April 26. If he pulls all this off, the Senator will then face his final hurdle: California’s primary on June 7 with 546 delegates, more than 11% of the Democratic total.

Playing Against a Stacked Deck

Sanders’ quest is so daunting not as much because of the strength of Clinton but because the Democratic Party stacks the electoral deck long before the first contest.

Fearful of a populist but — in its eyes — unelectable candidate, such as George McGovern in 1972, the Democratic establishment mandated 712 “superdelegates” from the party’s Congressional representatives, governors, and National Committee members.

Unsurprisingly, most of those superdelegates quickly endorsed Clinton rather than Sanders, an independent in Congress for 36 years before joining the Democrats in 2015. Currently, Clinton has 461 of the unelected delegates, compared to her rival’s 25.

That head start for Clinton means that a simple majority for Sanders in each and every primary and caucus is not enough. To claim the nomination, he needs about 60% of the remaining delegates.

A Sanders booster might argue that a third of the superdelegates have not made a decision yet, and the others can always switch their endorsement if they suddenly Feel the Bern. After all, the system did not prevent that switching behind Barack Obama in 2008 when he became more than an exciting underdog in the Democratic race.

But Sanders’ position is far different from the 2008 Hope-and-Change. Obama was a freshman Senator from Illinois, but he was still marked as part of the Democratic establishment, having made his entry with a dynamic speech at the 2004 Convention. He has always been — despite the claims of his detractors — in the center of the party, whereas it is Sanders who is the socialist.

Put bluntly, Obama wanted to reclaim the White House from the Republicans. Sanders wants to take it from a Democratic heiress-apparent.

The Chance for Upset

Still Sanders has already cleared obstacles that his opponents thought were too high. He has won outside the Northeast. He has won in primaries rather than caucuses. He has now won in a big state — specifically, a big state in the Rust Belt.

So can he jump even higher? Michigan offers a guide to the answer.

Sanders’ surge has always been carried by younger voters, but the tide was even higher in Michigan. He won 81% support from those aged 18-29. Even more importantly, that group turned out in greater numbers than expected: 19% of voters were under 30, the same percentage as those over 65, who predominantly support Clinton.

Still, on its own, the youth vote could not bring Bernie victory. He also overtook Clinton among the 30-to-44 group, winning by double digits. He chipped away at her advantage among African-Americans voters, winning 31% in contrast to only 16% in Mississippi on the same night.

But what is the message that brought these groups together, and could do so again?

As an advisor to Hillary’s husband Bill said during the 1992 campaign, “It’s the Economy, Stupid”. For Sanders, it has to be about discontent with that economy going back to the 2008 financial debacle and going forward to proposed trade deals arousing concern among many workers.

Sanders’ message about the response to 2008, with its bailout of banks and a stimulus seen to reward many of those who got the US and the world into the mess, appears to be striking a chord. In a takeaway line from last week’s debate in Michigan, he declared, “Let the billionaires themselves bail out Wall Street. It shouldn’t be the middle class of this country.”

However, it is on trade that the Vermont Senator may get his greatest traction. Because large unions are often seen to be in alliance with the Democratic establishment, Michigan was assumed to be a lock for Clinton.

But workers didn’t quite see it that way, with Clinton slipping because of her support of international trade agreements. About 60% of the voters said the trade takes away US jobs. Among that group, Sanders had a 20% margin over Clinton.

That advantage complemented Sanders’ edge with those who supported his criticism of banks, financial institutions, and corporations. Of the one-third who said Clinton is too pro-business. Sanders won more than 80%.

A Valiant and Necessary Campaign

So Sanders has to weld together his established advantage with young voters with a wider appeal to over-30s and workers who are concerned about America’s economic direction, as well as getting some inroads into Clinton’s fortress of African-American voters.

That is near-impossible in the Southern states, but almost all of them have now held their contests. The Rust Belt now is the battleground, albeit one where Bernie’s troops have to overtake Clinton forces who have been established for months.

However, if the chances are slim, the effort is far from quixotic. Sanders has brought dynamism into a Democratic race which had been designed as a procession for Clinton. Doing so, he has made the party address social and economic concerns that will animate the final campaign this autumn. He has put it to the test that its story and Clinton’s is not just “for voting for every disastrous trade agreement, and voting for corporate America”.

And, despite the sharp rhetoric he will probably do so from the standpoint of unity, rather than division. The Democratic platform will take on some of Sanders’ ideas — indeed, Clinton has already done so — as attention turns to defeating Donald Trump’s own blend of “Make America Great” and denunciation of foreigners.

It may not quite be “The People’s Revolution”, but it will be a feel-good achievement that few would have thought possible last April, when Sanders announced his candidacy to a clutch of reporters: “This country today…has more serious crises than at any time since the Depression of the 1930s.”