Bernie Sanders is building momentum in the Democratic primary contest that is elating his base and alarming many in the party establishment who believe his lead could soon become insurmountable.
“The results are clear,” said Julian Zelizer, the Princeton University professor and historian. “Sanders is a strong and clear frontrunner — and his support keeps growing.”
In the Nevada caucuses on Saturday, Mr Sanders swept most voter demographics, performing well among both men and women, whites and Latinos, and voters under the age of 65, particularly young people. His victory comes on the heels of a first-place win in New Hampshire and a neck-and-neck finish with Pete Buttigieg in Iowa. It will give him a huge boost going into the South Carolina primary next Saturday, and the blockbuster Super Tuesday vote three days after that.
Moderate Democrats have argued vociferously against Mr Sanders, claiming that his policies, which include “Medicare for All” universal healthcare, are too far-left and will turn off voters in the general election.
Mr Buttigieg, the former South Bend, Indiana mayor, urged Democratic voters to take a “sober look” at what it would mean for their party if it chose to put forward Mr Sanders as its nominee.
“Senator Sanders believes in an inflexible, ideological revolution that leaves out most Democrats, not to mention most Americans,” Mr Buttigieg told supporters shortly after Mr Sanders’ Nevada win.
“Democrats need to wake up,” said Matt Bennett, co-founder of the centre-left think-tank Third Way and a vocal critic of Mr Sanders. “Sanders is getting close to running away with the nomination. If he does, we are in serious trouble in the [general election], both up and down the ballot.”
Yet for Mr Sanders’ supporters, the win in Nevada was proof that while moderate Democrats have built their campaigns on the argument of electability, it is Mr Sanders who has proven he can actually win and gradually expand his base of support.
In Nevada, the most diverse state to vote in the primaries thus far, Mr Sanders performed especially well among Latino voters, despite a clash with the state’s powerful culinary union in the lead-up to the vote. He also narrowly won among Democratic voters who described themselves as either moderate or conservative, narrowly beating out former vice-president Joe Biden.
“We have just put together a multigenerational, multiracial coalition, which is going to not only win in Nevada, it’s going to sweep this country,” Mr Sanders told supporters at a victory rally in Texas.
Monica Smith, a worker at Las Vegas’s Bellagio casino and a member of the state’s culinary union, said she had ultimately decided to vote for Mr Sanders because she considered him “the most viable”.
“When it comes down to what we’re here to do, we’re here to beat Donald Trump,” she said. “That’s our bottom line.”
Crucial for Mr Sanders’ path forward will be Super Tuesday, on March 3, when 14 states will vote, with one-third of total delegates up for grabs.
Polls show Mr Sanders to be ahead by double-digit margins in California, which allocates about one-tenth of total delegates. Candidates there must receive at least 15 per cent of the vote to be viable to receive any of the state’s delegates.
According to RealClearPolitics average of polls, Mr Sanders is the only candidate polling above 15 per cent in the state, meaning there is a chance all 416 of California’s delegates could go to him.
“You could very well see a scenario in California where Sanders gets all the votes and at that point not only does he have a prohibitive lead, but if the centre [of the party] says at that point ‘we have to organise to stop Bernie and we’re going to do that at the convention somehow’,” said David Rothkopf, a political scientist who served in the Clinton administration. “It would produce a massive crisis in the party.”
For now, moderate Democrats still appear divided about which of the candidates who share their ideology should serve as the centrist alternative to Mr Sanders. By the time the field winnows, it might be too late, said Mr Rothkopf.
“If you’re a centrist, you have 10 days,” he said. “You have from now until Super Tuesday and either a bunch of people drop out and there is some move to unify around somebody. Or it’s going to be a runaway [win] for Sanders.”