A few days before the Feb. 1 Iowa caucuses, Brad Martsching was barreling down a Pennsylvania highway, hoping to unload his eighteen-wheeler in time to get back home to Indianola, south of Des Moines, and participate for the very first time in the opening ritual of the presidential primary process. Martsching, 46, had settled on Ted Cruz over Donald Trump, but was mostly nursing his disgust at Republican leaders. “I’m a conservative. I want the Constitution to be our law, not political correctness,” he said. “I want a smaller government with less control of our personal lives and more control of our border, our finances, and our safety as a nation.” Republican lawmakers kept frustrating him by ignoring their campaign promises. “We get people that run as conservative and even get Tea Party support—they wear that lapel pin proudly,” he said. “But when they leave for Washington, they leave it on their dresser at home.”

Martsching was fed up. A lot of other Iowans were, too. So they handed a victory to Cruz, who infuriated Republican leaders by engineering the 2013 government shutdown. And they made Trump, who’s equally unpopular in Washington, a close second. Add Cruz’s 28 percent to Trump’s 24 percent, and more than half of caucusgoers supported an outsider openly despised by the GOP establishment. Voters had heeded party elders for decades by nominating establishment figures such as Bob Dole, George W. Bush, John McCain, and Mitt Romney. The Iowa result was nothing less than a revolt, and the message to Republican leaders unmistakable: Drop dead!

It’s easy to view this year’s Republican primary as a cult of personality and no more—the rise and fall of a colorful billionaire who stars in the greatest reality show on television. But what’s happening is much broader than Trump and Cruz. It’s an extension of a shift in Republican politics that’s been under way for several years. Although the media is portraying the outcome in Iowa as a repudiation of Trump, it’s better understood as a repudiation of the party establishment—just the latest in a series of uprisings dating to the 2010 election. At the congressional level, the GOP has already realigned itself to reflect this anger. Almost 60 percent of House Republicans were elected in 2010 or after. They’ve radicalized their party in Congress and driven out its establishment-minded speaker, John Boehner.

In the eyes of Republicans like Martsching, that isn’t enough. “Over the last six years, the nation has replaced almost all the liberals who voted for Obama’s programs with Republicans,” he said. “So why do they keep giving him things anyway? They’re simply not responsive. They have a different set of priorities. It’s crony capitalism.”

For all that the media fixated on Trump and Cruz, the Iowans I spoke to were more preoccupied with a litany of economic and cultural frustrations. The same complaints came up again and again—so did their antipathy toward their own party’s leaders in Washington, who, just about everyone agreed, had stopped listening to them entirely. “Out here in the cheap seats, those people are the ones that are our biggest enemy,” said Myron Brenner, 61, a heavy-equipment operator in Wallingford who caucused for Cruz.

Cruz’s victory came as a mild surprise, in part because the last 10 public polls showed Trump winning by an average of 7 points, and in part because the media long ago cast the mogul as the lead actor in the Republican drama. Trump’s outlandish behavior and attacks on Muslims, immigrants, China, the Obama administration, and the “idiots” and “losers” opposing him made him seem like the embodiment of the anger and anxiety coursing through the Republican electorate. “I want to win Iowa,” Trump declared in Cedar Rapids on caucus day. “It’s going to send such a great message that we’re not going to take it. We’re not going to take it anymore.”

While Trump didn’t prevail, his message did: Cruz, and even third-place finisher Marco Rubio, echoed the same dark themes of nativism, treachery, and corruption. Like Trump, Cruz presented himself as the savior of disaffected working-class Americans who are routinely sold out by a “Washington cartel” that encompasses the leaders of both parties. (In a sense, Cruz won by running as a pious Trump with a better turnout operation.) Rubio engineered his last-minute surge by abandoning the sunny “New American Century” pitch he’d been making for months and appealing to “all of us who feel out of place in our own country.”

Iowa doesn’t decide the nominee. But it does send a clear signal about the direction a party’s taking. According to the entrance/exit poll, 65 percent of GOP caucusgoers believed that “new ideas and a different approach” were the most important qualities a candidate should possess. Cruz and Trump have distinctive styles—Cruz touts his ideological purity, Trump his personal strength—but both offer the same basic diagnosis of what’s ailing the country, who’s to blame, and what must be done to fix it.

That they’re resonating so strongly with voters suggests that the same wave that’s swept through Congress since 2010 is now engulfing the presidential campaign. As Patrick Buchanan, the former Nixon aide who won a 1996 New Hampshire primary upset by running as a populist proto-Trump, told the Washington Post: “The anger and alienation that were building then have reached critical mass now, when you see Bernie Sanders running neck and neck with Hillary Clinton in Iowa and New Hampshire and Trump and Ted Cruz with a majority of Republican voters. Not to put too fine a point on it, the revolution is at hand.”

The question now is what effect this revolution will have on the Republican Party. Will its voters nominate Cruz or Trump, each of whom party insiders believe could suffer a loss that would rival Barry Goldwater’s landslide defeat in the 1964 election? Will the party break apart if they do? Or will Rubio or some other establishment-friendly alternative manage to harness this anger and prevail? And what then?

It’s too soon to say. But a Republican electorate increasingly composed of working-class white voters who suffer disproportionately from stagnant wages and dim prospects appears to have lost faith in party leaders more interested in pursuing high-end income tax cuts and immigration reform. Given the political and economic climate, history offers an intriguing framework for what could happen next.

In 1955 the famed political scientist V.O. Key published “A Theory of Critical Elections,” an article popularizing the idea that certain elections in American history were more meaningful than the rest because “the decisive results of the voting reveal a sharp alteration of the pre-existing cleavage within the electorate.” This became known as realignment theory. Realigning elections, Key believed, create “sharp and durable” changes in the polity that can last for decades.

American historians generally see five or six elections as realigning: 1800, when Thomas Jefferson’s victory crippled the Federalist Party and shifted power from the North to the South; 1828, when Andrew Jackson’s win gave rise to the two-party system and two decades of Democratic control; 1860, when Abraham Lincoln’s election marked the ascendancy of the Republican Party and the secessionist forces that led to the Civil War; 1896, when William McKinley and a new urban political order were swept into power by a depression and industrialization; and 1932, during the Great Depression, when Franklin Roosevelt’s triumph marked the beginning of three decades of Democratic dominance. Some historians argue that Ronald Reagan’s 1980 victory, primed by the stagflation of the 1970s, was also realigning.

Political scientists don’t all subscribe to this theory. It’s more of a conceptual scheme, anyway, since it offers little in the way of predictive power. But it’s a useful way to analyze political change across elections. Academics generally say two major preconditions must be present for a realigning election to occur. First, as the political scientist Paul Allen Beck has written, party loyalty must be sufficiently weak that the electorate is “ripe for realignment.” Second, there must be a triggering event—a “societal trauma,” Beck calls it—such as a war or a depression. Throughout history, wars and depressions have failed to cause big shifts because voters weren’t primed for one. Likewise, periods of voter alienation didn’t cause enduring swings between the parties because there was no triggering event. But when the proper conditions are present, they produce “concentrated bursts of change” that cause turmoil in the presidential nominating process, the political scientist Walter Dean Burnham wrote.

Realignment theory was popular in the 1960s and ’70s, but it’s faded since, because the American electorate has become polarized to the point where long periods of single-party dominance no longer happen. But realignments can still occur. They’re just more likely to happen within parties, rather than between them.

In hindsight, the 2010 election looks like it may have set off, or at least accelerated, a shift within a Republican Party that, in the 30 years since Reagan took office, has oriented itself around free markets, a smaller safety net, foreign adventurism, and low marginal tax rates for the wealthy. As Cruz and Trump have demonstrated, a large subsection of Republican voters—possibly a majority—are no longer satisfied with this arrangement.

Both of the necessary preconditions for a realignment are present. The Great Recession of 2007-09 supplied the catalytic societal trauma: Pew Research Center data show Republican anger at Washington spiked before the 2010 election and has never fallen. And no one who’s turned on a television or attended a Republican rally can doubt for a minute that attachment to party leaders is at a low ebb.

Even if you don’t subscribe to realignment theory, the 2010 election is still a useful demarcation in understanding the Republican primary campaign. Every candidate who’s caught fire this cycle came to political prominence after 2010: Trump, Cruz, Rubio, Ben Carson, and Carly Fiorina all fit this bill. Those who have disappointed the most are generally products of the era before then: Jeb Bush, Chris Christie, and John Kasich come to mind.

Looking back, it’s clear that the forces upending the 2016 presidential primaries were also present in 2012. We just weren’t looking for them. As they did this cycle, Republicans toyed with nominating goofy flimflam artists such as Herman Cain and Michele Bachmann before settling on former Pennsylvania Senator Rick Santorum as the main rival to Romney, the establishment favorite.

Santorum’s outspoken social conservatism has always caused him to be viewed as a candidate of the religious right. But in 2012 he spoke to many of the same blue-collar anxieties that Trump and Cruz have tapped into, proposing a mix of protectionism, infrastructure spending, revived manufacturing, and a purifying sweep of corrupt Washington leaders as the remedy for economic and cultural stagnation. “It was certainly, at the very least, a precursor to 2016,” says John Brabender, Santorum’s chief strategist.

Santorum’s most striking TV ad that year (“Rebellion”) was one Brabender created that showed working-class voters being blindfolded and marched off a cliff by an executive with a bullhorn—a stand-in for the GOP leadership. “The establishment is once again telling us to fall in line,” a narrator said, “and vote for their backroom, handpicked moderate candidate.” Santorum went on to win 11 states.

The intervening years, Brabender believes, have only deepened this voter sentiment: “People are no longer saying ‘Who am I supposed to vote for? Lead me there.’ Everything since then has solidified that feeling of being abandoned and made them more angry.” It’s no wonder audiences always respond to Cruz’s shouted stump-speech admonition, “If you see a candidate who Washington embraces, turn and run!”

As the primaries took shape over the past six months, the big fight has been less oriented around ideology and more oriented around class. According to the Iowa entrance/exit polls, Cruz and Trump were, respectively, the top choice of “very conservative” and “moderate” caucusgoers. Rubio won “somewhat conservative”—those in between. Where Trump and Cruz divide most sharply from Rubio is in their supporters’ education level. Rubio handily won voters with a postgraduate degree; Trump and Cruz performed best among voters with a high school degree or less (Trump) or some college (Cruz). A Cruz or Trump win would signify that working-class voters will no longer be forsaken by their party leaders in favor of a class of wealthy campaign donors.

Perhaps, as they did in Iowa, Trump and Cruz will stay focused on each other, allowing the new, angrier Rubio to eke out a win. Regardless, the signal Republican voters are sending is clear. From here on out, the contest will be about which candidate should deliver that message to Washington.

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