That sound you heard over the weekend was thousands of centrist pundits crying out in panic as it became apparent Sen. Bernie Sanders (I-Vt.) stands a real chance of becoming the Democratic nominee for president.

"There is no sugarcoating the results," The Washington Post's Ruth Marcus grumped Sunday after Sanders won the Nevada caucuses in impressive fashion.

"In 30-plus years of politics, I've never seen this level of doom," Third Way's Matt Bennett told Politico.

And on MSNBC, Chris Matthews — somewhat hysterically — likened Sanders' victory the Nazi defeat of the French army in 1940. "It's over," he pronounced.

Actually, it's not over. Yes, Sanders' accomplishments so far are impressive. But the Super Tuesday contests loom next week, when 14 states will cast their ballots then. That's a lot of voters, and a lot of convention delegates, who will be making their preferences known all at once. Sanders might emerge from Super Tuesday with an even larger lead over his rivals — but he might not. It will, however, definitely be easier to assess the state of the Democratic race after nearly a third of the nation has a chance to weigh in on the potential nominee.

That said, a look back at some recent presidential elections can give us context for Sanders' achievements thus far.

It's not 1992 anymore: For most of the past 50 years, Democratic presidential politics have been driven by fear of nominating a candidate too far to the left of the electorate. Richard Nixon blew out George McGovern in 1972; Ronald Reagan destroyed Walter Mondale in 1984. A whole generation of Democratic leaders — Bill Clinton foremost among them — learned to tack to the middle. Yes, Clinton pursued universal health care after winning in 1992, but he was also tough on crime and an unabashed capitalist, closing the deal on NAFTA and signing the repeal of Glass-Steagall legislation that had heavily regulated banks since the 1930s.

Sanders' success, of course, defies that Clintonian logic. Naturally. There is a whole generation of 30-something voters who weren't even born when Michael Dukakis took his infamous tank ride in 1988. The Democratic losses those voters remember — Al Gore Jr. in 2000, Hillary Clinton in 2016 — seemed to have more to do with the esoteric nature of the Electoral College system than with any ideological extremism. They simply don't have the muscle memory to fear losing an election because the Democratic candidate veered too far left.

It's not 2000 anymore, either: By the turn of the century, the consensus of both the Republican and Democratic parties was so centrist that voters complained they couldn't really tell a meaningful difference between Al Gore Jr. and George W. Bush. Both were sons of power and privilege — Gore's dad was a senator; Bush's was the previous Republican president — and most meaningful questions of the election seemed to boil down to style: Was Gore's suit "alpha" enough? Could you get a beer with Bush? Voters further from the ideological center turned to Ralph Nader on the left and Pat Buchanan on the right for alternatives. Bush then spent eight years proving less moderate than advertised.

The election of 2020 is shaping up as an inversion of the Gore-Bush contest. The differences in a potential election campaign between Sanders and President Trump couldn't be starker. Sure, both are septuagenarian New Yorkers. But Trump runs on a record of tax cuts for the rich while Sanders wants to offer a range of new and expanded government services for poor and working class Americans. This year, it's the centrists who increasingly find themselves on the outside looking in.

But maybe it is still 2016, a little bit. Trump's victory over Hillary Clinton — while it comes with an Electoral College asterisk — surprised the establishment, and set off a search for answers that still hasn't quite abated. Many on the left chalked the result up to sheer racism, a backlash from white America against eight years of governance by a black man.

It's a fair theory, but the rise of a lefty populist movement to support Sanders suggests that story is incomplete. Sanders' voters see a world where education, housing, and health care are increasingly unaffordable. They fear losing ground in their own lives and the lives of their loved ones — and are voting accordingly.

Sanders could still lose momentum. But after his strong showing against Hillary Clinton in 2016 and his powerful start to the 2020 race, it is probably time for activists and observers to stop panicking at the prospect of his success and figure out how that can help them better serve a restless public.

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