When Vermont Senator Bernie Sanders announced he was seeking the Democratic nomination for president a year ago, his odds seemed next to impossible.
The coronation of former Secretary of State Hillary Clinton was already in full swing and his left-wing, “democratic socialist” values clashed with the status quo in both parties and the mainstream media.
Following his victory in the Oregon primary this week, securing the nomination of his new party after years of serving as an independent still seems highly unlikely, but he’s gotten closer than anyone thought he would – and technically, he’s not out of the running yet.
Despite Clinton having a much lower “favorable” rating, and Sanders doing much better against Trump in the polls, he still trails by a large number of delegates.
Looking at the math, Clinton only requires 615 more delegates to win the nomination, whereas Sanders needs 889.
However, when superdelegates are taken into account, the former Secretary of State is just 90 shy of the magic number, while the Vermont Senator has to somehow come up with another 850.
A total of 939 delegates, both pledged and super, are still to be decided in the remaining primaries.
Here are the five scenarios that could lead to America’s first democratic socialist president.
Scenario 1: Landslide in remaining primaries
Clinton currently has a total of 1,768 delegates to Sanders’ 1,494, so Sanders would need to 'run the table' and win no less than 68 percent of those remaining, not counting the superdelegates that have already declared for Clinton, according to AP.
READ MORE: 'Bernie Sanders is not winding down his campaign'
Key states for Sanders will be California, with 546 delegates up for grabs, and New Jersey with 142. Without a big win in both of these, anything short of a “West Wing” scenario (see below) makes it impossible for the former mayor of Burlington to win.
If he does pull off a sweep, superdelegates would have to be willing to follow the mandate of voters, riding the wave against their first choice without fear of inciting the wrath of the DNC Gods who gifted them with their cushy, powerful gigs.
Scenario 2: Wins California, but not New Jersey
While none of the roads to the nomination are straightforward for Sanders, if he were to win California, it’s certainly a less rocky road.
During a speech in the Golden State on Tuesday, Sanders described this final couple of weeks of campaigning as “the beginning of the final push to win California.”
While there have been a number of polls detailing the likely outcome of the state’s primary, they aren’t particularly useful since none have been conducted this month.
Polls covering the second half of April show Clinton leading by as much as 19 percent – and as little as 2.
According to RealClearPolitics, the average lead predicted for Clinton up until the end of April puts her just 9.7 percent above Sanders – a drop of 30 points since the campaign started last year.
Then again, even a new poll can be unreliable. A May 9 survey in Oregon gave Clinton a 15 percent lead, but in reality Sanders won by 12 percent – 56 to 44.
Another important state for Sanders is New Jersey, which pollsters also see as a sure win for Clinton.
The most recent data shows Clinton with an average lead of 17 percent, according to RealClearPolitics.
If this is to be taken at face value, with Sanders securing only 38 percent of the vote, and assuming all other primaries went his way, Clinton would still have a narrow lead going into July’s convention.
The superdelegates would decide the winner, and like Scenario 1, a great number would need to switch to Sanders for him to beat Clinton.
Scenario 3: Superdelegates switch at Convention aka the “West Wing Scenario”
Neither candidate can win with pledged delegates alone. Only the 712 supers can put either one over the top.
The combination of governors, senators, representatives, DNC members, and “party elders” can back anyone they want, even someone who wasn’t on the ballot during the primaries, and they can switch their preference on the convention floor, as dramatically portrayed in a West Wing episode aptly-named “2162 Votes.”
Sanders and his supporters hope that if he wins the upcoming primaries, particularly California, the resulting momentum will inspire superdelegates to shift to his camp ahead of, or dramatically during, the convention in Philadelphia this July.
It would also help if he gave one helluva speech.
Currently, 525 superdelegates are backing Clinton.
Most notably, former president Jimmy Carter and 2000 popular vote winner Al Gore are still undeclared.
Sanders hopes he can eat into that number, but it’s a tall order, particularly given his outsider status in the party.
Despite his win in Oregon and virtual tie in Kentucky, his job got a little harder this week after one of his Virgin Islands superdelegates switched sides.
Another possible incentive for superdelegates to change their allegiance would be the emergence of further developments in Clinton’s email server scandal.
The ongoing FBI investigation is headed by her former boss, President Barack Obama, so political considerations could delay any new revelations until after the convention and, Democrats hope, after the general election too.
Scenario 4: Run as an Independent or Green Party candidate
Most Americans, particularly young people, would love to see this situation develop if Sanders falls short of the Democratic nomination.
READ MORE: Nearly every young American voter wants an independent candidate on the ballot – poll
While some of his supporters categorically reject the idea of switching allegiance to Clinton if he doesn’t get the nomination, the candidate has shown little interest in going back to his indie roots.
One online petition calling on him to run as an Independent has garnered over 27,000 signatures, while another calls for him to join forces with Jill Stein, who is hoping to secure the Green Party’s nomination at its convention in August.
Stein tweeted in March that America's only anti-austerity, anti-war, pro-environment, social justice party has “always been open to talking with Bernie Sanders about ways to move our shared goals forward.”
This may be his only real alternative if he wants to carry the movement all the way to November.
The Greens have ballot access in most states, as well as access to federal matching funds.
Stein echoed these sentiments in a letter to Sanders in April, when she said “their campaigns could work together to win a progressive political revolution in the United States.”
While they would need to resolve their differences on Israel and drones, they would be closer on most other issues than Sanders is with centrist Democrats like Clinton.
Scenario 5: Clinton-Sanders ticket
While the coveted Oval Office spot would still go to Clinton, Sanders could run as her vice president.
In an interview with Face the Nation in early May, Clinton seemed to indicate this hasn’t been completely ruled out, noting she saw “a great role and opportunity for him and his supporters to be part of that unified party, to move into not just November to win the election against Donald Trump, but to then govern based on the progressive goals that he and I share.”
While most progressives including Sanders dispute the former 'Goldwater Girl's' left-wing credentials, he hasn’t entirely ruled out such an offer either, telling CNN that he would be willing to meet Clinton after July’s convention to “sit down and talk and see where we go from there.”
Whatever happens in the next two months, a messy – and long – convention may be in store, possibly reminiscent of the 1972 DNC in which George McGovern, an anti-war senator from a tiny state, made his acceptance speech at 2 a.m.
Worse, there could be a rebellion on the convention floor and/or in the streets of Philadelphia, like Chicago in 1968, when “the whole world” was watching.
Then again, President Barack Obama could swoop in to save the day with one of the last high-profile speeches of his political career - and pick the successor he wants.