Matt Slocum / AP

The most important message from this year’s tumultuous presidential primaries may be that millions of voters in both parties have grown sufficiently disenchanted with conventional political options to vote for candidates who not long ago would have been considered beyond the pale of viable choices.

20 or even 10 years ago, both Donald Trump and Bernie Sanders might have struggled to advance beyond the margins of their parties. Yet after this week’s five primaries, Trump has drawn just over 10 million votes and Sanders 9.3 million. Both have built followings that are not only large but also more impassioned than those attracted by their more traditional rivals, from Ted Cruz to Hillary Clinton.

Each man’s support has displayed limits. Sanders’s four losses on Tuesday leave him confronting the grim math of Clinton’s virtually inevitable nomination. And while Trump’s emphatic five-state sweep solidified him as the clear front-runner for the GOP nomination, polls consistently show him trailing Clinton in a prospective general election.

But whether or not either man ultimately claims the White House, their rise still signals a searing vote of no-confidence in the results produced by the nation’s political leadership. Though they embody very different political impulses, Trump and Sanders have been propelled by a common torrent of discontent that more conventional leaders will ignore at their peril. “People feel like the way things have been running for the last couple of years, if not decades, has not been working out for them,” the Republican pollster Kristen Soltis Anderson said. “They have been using traditional remedies to address an illness and it’s not really working so all of a sudden the experimental treatment with all the crazy side effects starts looking a lot more appealing.”

That’s particularly true among the groups central to each man’s coalition: working-class whites for Trump, and members of the Millennial generation for Sanders. Trump has now won whites without a college education in 21 of the 25 states with exit polls, often by imposing margins; even when the GOP field was more crowded, he routinely carried about half or more of them, and those numbers soared to around two-thirds on Tuesday in Connecticut, Maryland, and Pennsylvania.

Sanders has also shown a surprising appeal to the smaller number of blue-collar whites who still participate in Democratic primaries. But his coalition is centered on the massive Millennial generation, which this year will roughly equal the baby boom as a share of eligible voters. In 23 of the 25 exit-polled states, Sanders has carried voters younger than 30. One cumulative analysis of all exit polls found that through the New York primary he had won 70 percent of those younger voters, a substantially higher percentage than even President Obama carried against Clinton in 2008. Sanders posted even larger numbers among young people in this week’s contests.

The right question may not be why so many blue-collar whites and Millennials are flocking to such nontraditional candidates, but why it has taken them so long to find these alternatives.

On many measures, both groups are among the nation’s most economically strained. Hourly wages for white men with only a high school education, adjusted for inflation, were virtually no higher in 2011 than in 1989, and actually lower than in 2000, according to calculations by the Economic Policy Institute, a liberal think-tank.  Meanwhile, since 2000, as the EPI noted recently, inflation-adjusted wages have remained stagnant for young college graduates, and declined slightly for young workers with only a high-school degree. Slow wage growth, combined with mounting educational costs, has left this generation struggling to cross the key mileposts of adult life: As the Federal Reserve Bank of St. Louis has reported, “college-educated young adults in 2013 had higher debt burdens, lower total asset holdings, and lower net worth than their counterparts had in 1989.”

Trump and Sanders are far more different than alike. Yet their responses to this widespread distress share some similar impulses. Both are skeptical of free trade. Both portray the political system as hopelessly infected by special interests. Both explain their supporters’ distress by pointing to shadowy culprits: for Sanders, “the billionaire class” and for Trump, undocumented immigrants, foreign manufacturers, and Muslims.

Both are also offering solutions that have little prospect of success in today’s closely divided political environment. Trump’s call for mass deportation of undocumented immigrants, a temporary ban on Muslim migration, and huge tariffs on foreign imports would face formidable resistance even in a Republican-controlled Congress. Likewise, even many congressional Democrats would recoil from a Sanders agenda that would push government spending to its highest level (as a share of the economy) since World War II to fund government-run single-payer health care, universal free public college, and widespread student-debt forgiveness, among other things.

It’s easy to find the flaws in these ideas, and also to deride the toxic racial signaling in Trump’s campaign. The harder challenge is to find politically plausible responses to the anxieties swelling the audience for Trump and Sanders alike. More traditional voices in both parties are still most likely to set Washington’s 2017 agenda. But in the streaking comet of these two campaigns, they should see a clear warning that continued partisan stalemate and inaction will ensure the volatile emergence of more voices determined not to renew the existing political order, but to raze it.

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