By focusing so much on the candidates, consultants, and donors in political coverage, it's easy to overlook the most important element in the political process—the voters. And at a time when Washington has prospered but much of the country has struggled, it's easy to forget just how disaffected the American electorate is. For nearly all of the past decade, Americans have consistently believed that the country was headed in the wrong direction and have grown alienated from their elected leaders.

Consider: Since 2006, there have only been seven public polls (out of thousands) showing that more people believe the country is generally headed in the right direction than the wrong direction. In recent years, the "right-track" optimists have rarely hit even the 30 percent mark. In the year before the two most recent open presidential elections (2008/2016), nearly three-quarters of voters surveyed in the NBC/Wall Street Journal poll said they wanted the next president to take a different approach than his or her predecessor.

It has been a dismal decade for most Americans. Whether it's government incompetence (Hurricane Katrina, the Veterans Affairs' deadly lapses in medical care), economic recession followed by a slow recovery, deadly struggles in managing post-war Iraq, or the increasing threat of terrorism from a brutally repressive enemy, there's been good reason for voters to distrust their government and its political representatives. Indeed, since 2006, we've seen wave elections occur in four out of the past five cycles. Democrats capitalized on the public's anger to take back control of Congress in 2006 only to hit historic lows in representation across the country eight years later. If the United States had a parliamentary system, the government would be facing routine votes of no confidence.

So it's no surprise that this year's presidential campaign has been as unpredictable as ever. That happens when voters feel that government isn't working for them, and they've been feeling that way for nearly 10 straight years. In past elections during times of voter alienation, the unexpected happens. In 1976, the first campaign after Watergate and amid rising crime and inflation, a little-known Georgia governor (Jimmy Carter) came out of nowhere to win the Democratic nomination and the presidency. That same year, a Republican president (Gerald Ford) was nearly unseated by a conservative insurgent (Ronald Reagan) that few pundits took seriously at first. In 1992, in the middle of a recession, Democrats chose a fresh-faced Arkansas governor (Bill Clinton) while Republicans saw a populist (Pat Buchanan) threaten their president (George H.W. Bush) in early primaries—with a billionaire winning 19 percent of the vote running as a third-party candidate (Ross Perot).

Sound familiar?

This is why the expectations of a Jeb Bush-Hillary Clinton 2016 presidential election never made much sense—it couldn't be more disconnected with voter sentiment. Bush's candidacy still hasn't captured the imagination of most GOP voters, and the Democrats' unification behind a Clinton campaign was as much a reaction to the lack of younger, up-and-coming successors to Obama as it was to genuine grassroots enthusiasm for the former secretary of State. At a time when anti-Washington, antiestablishment feelings are near all-time highs, why would both parties nominate candidates with political bloodlines who've benefited from their family connections? All the campaign money in the world can't change fundamental vulnerabilities. It shouldn't be too surprising that Donald Trump—not to mention all the outsider candidates, such as Ben Carson and Carly Fiorina—are surging in national polls.

Not surprisingly, Bush and Clinton's favorability ratings are consistently among the worst of the candidates running for president. Clinton's numbers outside the hardcore Democratic base are so poor that she barely looks more electable than Trump, according to the latest round of national and swing-state polls. She loses to Trump in a head-to-head matchup in Florida, according to Quinnipiac's August survey. And while Bush is only winning lukewarm support from rank-and-file Republicans, he's also struggling to make inroads with independents. Last month's NBC/Wall Street Journal poll found Bush's net favorability at -14, offering little improvement over the GOP's battered brand (at -16). If their names weren't Clinton or Bush, they'd look like also-rans for the presidency, not frontrunners. Their favorability ratings are well behind Marco Rubio, Scott Walker, Joe Biden, and Bernie Sanders.

On the campaign trail, these vulnerabilities are playing out. Bush has proven to be a rusty campaigner, struggling to disassociate himself with the legacy of his brother. He's facing other establishment-friendly challengers who offer similar messages but without the hereditary baggage: Ohio Gov. John Kasich offers a stylistic contrast, while Sen. Marco Rubio of Florida provides a generational one. Clinton has projected a sense of entitlement on the campaign trail, avoiding interviews with the national media and carefully stage-managing her public events. It's that very mentality that led to her decision to use a private email server as secretary of State, allowing her to conceal correspondence from the public. That's now causing her immense political trouble, given that she reportedly received and transmitted classified information in the process—not to mention possible legal trouble down the road, given the FBI's active investigation.

If the wide-open Democratic primaries of 1976 and 1992 offer any lessons for the Republican Party, it's that dark horses usually emerge under difficult times for the country. Trump is certainly taking advantage of that antiestablishment sentiment now, but as the primaries draw closer, it's more likely the party will rally behind an alternative with a little governing experience. Bush is hoping to be that candidate—he's now directly confronting Trump on immigration—but he'll find it challenging to be seen as the outsider that voters say they want.

But if those elections offer any relevant parallels, it's the governing Democratic Party that has the most to be worried about. In both elections, Republican presidents faced surprisingly serious challenges from the base, and the divisions foreshadowed serious general election problems. With the field seemingly cleared for her, Clinton looked as close to a lock for the nomination as any recent candidate. Now she's trailing socialist Sen. Bernie Sanders in New Hampshire and faces the real threat of Biden jumping in the race next month. The White House's unusually supportive comments this week towards Biden—a stark contrast from administration allies in the recent past—suggest there's real concern that Clinton's legal problems could become a political nightmare. At the very least, having Biden around is now looking like an essential insurance policy.

The notion that party leaders would be able to overcome the public's distaste for political insiders was always fanciful. Republicans should know better, given the turmoil the party has faced in numerous Senate and House primaries stemming from the disaffection of the party's grassroots towards the establishment. But by being the party in power, Democrats grew complacent towards the very forces roiling underneath them—and now they're stuck with a frontrunner who is entirely at odds with the politics of the moment.

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