Now it’s the Democrats’ turn to panic.

After a year in which the remnants of the Republican establishment has agonized over how to stop Donald Trump and now Ted Cruz, the Democratic party elders are now sweating bullets over Bernie Sanders.

Both the Trump tsunami and the Sanders surge were utterly underestimated by the media, for the same reason the political class is feeling desperate. The elites were blindsided by the degree of anger and frustration among voters of all political stripes.

The conventional wisdom at the start of 2015 was that Jeb Bush was a strong front-runner and Hillary Clinton was a lock. Now there is intense finger-pointing in Bush World for Jeb’s failure to emerge from single digits, and Hillary’s early-state strategy is being second-guessed as Sanders has raced to a huge lead in New Hampshire and threatens to beat her in Iowa.

What Bush and Clinton have in common, besides hailing from dynastic families, is that they were the safe choices expected to seize their respective crowns with vast sums provided by mega-donors. They are also 20th-century figures trying to retool themselves for a new century: Hillary first stood by her man in the 1992 campaign (and again during the Monica uproar of ’98), while Jeb first ran for Florida governor in 1994 and hasn’t held office since 2006. They’re both steady, serious and kinda dull.

Along come Trump and Sanders, neither one given a chance by the prognosticators, and they’re drawing bigger crowds and generating more enthusiasm than their rivals. Despite their vastly different ideologies, both are running against the establishment. Sanders, who spent his career as an independent, has even called Planned Parenthood and the Human Rights Campaign, which are backing Hillary, part of the establishment.

Trump, who doesn’t need to raise money, has shattered the rules of engagement and forced his rivals to be more aggressive on issues like illegal immigration; Sanders, who has raised far more dough than anyone imagined, has pushed Clinton to the left on health care and taxes.

Liberal commentators have enjoyed the spectacle of a GOP civil war, with some leading voices on the right declaring that the party will commit suicide by nominating Trump or Cruz, who as a freshman senator has alienated the establishment. But now it’s the Democratic elders who are freaking out about the possibility of a self-proclaimed socialist leading their ticket and dooming many down-ballot candidates.

“The Republicans won’t touch him [in the primaries] because they can’t wait to run an ad with a hammer and sickle,” Sen. Claire McCaskill, a Hillary supporter, told the New York Times.

In most campaigns, the insurgent candidate basks in the media spotlight but ultimately fades: Herman Cain. Rick Santorum. Howard Dean. Bill Bradley. Pat Robertson. Gary Hart.

But 2016 isn’t most campaign years. And what Trump, Cruz and Sanders have done is expose the weakness of the establishment, in both parties, along with the myopia of the media.

Howard Kurtz is a Fox News analyst and the host of "MediaBuzz" (Sundays 11 a.m. and 5 p.m. ET). He is the author of five books and is based in Washington. Follow him at @HowardKurtz. Click here for more information on Howard Kurtz.