DES MOINES, Iowa—Like a previously undiscovered earthquake fault, Donald Trump's presidential campaign is threatening to fracture the Republican electoral coalition along new lines. In the process he could disrupt both the demographic and geographic alignments that have defined previous races for the GOP nomination—and scramble the assumptions of his rivals about the coalitions they believed could power them to victory.

In both national surveys, and in polls across the key early states of Iowa, New Hampshire, and South Carolina, Trump's support is crossing almost all of the boundaries that have previously shaped Republican races, most prominently along lines of ideology and religious affiliation. He has replaced those old divisions with a new division that centers on education, building an advantage among working-class Republicans large enough to lead in virtually all surveys both nationally and in the critical early states.

"He has changed the electorate—at least the people they say they are going to be the electorate," said a senior strategist for one of Trump's rivals, who asked for anonymity in order to discuss internal campaign dynamics. "If we were dealing with the people who were voting in the past, you would see that division we've seen in the past. He has brought in something closer to a [Ross] Perot voter, more downscale, less educated, more on the fringes of economic security."

As the first voting approaches Monday in Iowa, Trump faces two overarching questions. One is whether his supporters, many of whom are less habitual voters, will turn out in the strength that polls project. Even if the answer is yes, Trump will eventually face a second key challenge: whether his polarizing personal style and message, particularly on race-related issues like immigration, will leave him with too low a ceiling of support to win if and when the race narrows.

But in this early stage, Trump's new coalition has allowed him to poll well across a surprisingly broad range of states and voters. "Trump has transcended all of this and it has surprised many of us, because these have always been ideological fights," said Scott Reed, the campaign manager for Bob Dole in 1996 and now a senior adviser to the U.S. Chamber of Commerce. "But the frustration and the anger at Washington has overshadowed a lot of ideology."

The results in Iowa Monday will mark the first test of whether Trump can translate his gaudy poll numbers into success at the ballot box. But in surveys, he's showing a demographic consistency and geographic reach without recent Republican precedent. Since South Carolina moved up in 1980 to become the third major competition behind Iowa and New Hampshire, no Republican candidate in a contested presidential primary has won all three. But NBC/Wall Street Journal/Marist Polls released last week showed Trump leading in all three states, with virtually identical patterns of support.

In recent cycles, ideology and religious affiliation have functioned as the most important divides in Republican nominating contests. Candidates have struggled, for instance, to win both Iowa and New Hampshire, because the former usually favors the candidates preferred by evangelical Christians and the latter tilts toward more secular and often more moderate economic conservatives.

Both John McCain in 2008 and Mitt Romney in 2012 followed the same broad formula for winning the nomination. Each man won about half of Republican voters who did not identify as evangelical Christians, and about one-third of those who did, according to a cumulative analysis by ABC pollster Gary Langer of all the exit polls conducted in each contest. Evangelicals and non-evangelicals each cast about half of the total Republican primary votes in both contests, Langer's analysis showed.

In a related pattern, Romney and McCain also ran better among more centrist voters than among conservatives. McCain won 55 percent of moderates in 2008, compared to just 35 percent of self-identified conservatives, according to Langer's analysis. No one has published a comparable cumulative analysis of GOP voters by ideology in 2012. But Romney carried voters who identified as moderates in 18 of the 20 states in which exit polls were conducted, and those who called themselves somewhat conservative in 15 of them. By contrast, in 14 of the 20 states with exit polls, most voters who identified as very conservative preferred Newt Gingrich or Rick Santorum over the former Massachusetts governor.

Most of the candidates running in 2016 built their plans on the assumption that these familiar grooves would again guide the race this year. Texas Senator Ted Cruz, in particular, organized his campaign around the goal of unifying conservatives, especially evangelical Christians, against a final rival to his left. As Cruz put it during this week's debate in Iowa: "I think anyone who is able to win in the Republican Party has to be able to bring together the disparate elements of the Reagan coalition. You've got to be able to bring together conservatives and evangelicals and libertarians, and stitch together a winning majority."

More centrist candidates, like Jeb Bush, John Kasich, and Chris Christie, have focused on coalescing the party's more moderate, usually white-collar elements. Marco Rubio has attempted to remain viable across all of the party's factions.

But Trump has disrupted all of these calculations by assembling an unprecedented coalition that barrels through the party's traditional boundaries.

"Everything was through the prism of the olden days and Trump not being a creature of politics … didn't think like that," said David Carney, a long-time New Hampshire based Republican strategist, who is neutral in this race. "That has freed him up. He is not trying to go after little segments; he is trying to go after everybody, with a very general message."

In early polling, Trump has erased most of the traditional divisions most of his rivals expected would define this race. Consider the NBC/Wall Street Journal/Marist Polls released last week in Iowa, New Hampshire and South Carolina. In all three of them Trump's support ranged only between 31 and 36 percent. All of those fit within the strikingly stable range of 31 percent to 37 percent backing for Trump evident in almost all national and early state surveys released over the past two weeks. (An exception to that pattern was the final Des Moines Register/Bloomberg Iowa Poll released Saturday night which put Trump ahead, but just at 28 percent).

In the South Carolina survey, Trump ran exactly as well among conservatives as moderates. In the Iowa and New Hampshire surveys, he ran a slim five points better among conservatives than moderates. In all three states, Trump performed nearly as well among evangelicals as he did among non-evangelicals. His numbers among religious conservatives also virtually equaled his showing among other voters in the most recent national polls by NBC/Wall Street Journal and Fox News Channel. In all of these surveys, Trump's numbers among likely voters who identify as Republicans and those who call themselves independents vary only very modestly as well. Some surveys do show a gender gap, with Trump running better among men, but in many of the recent polls, he is equally strong among women.

The most consistent dividing line in responses to Trump is education. That was a telling differentiator in 2012, too: Romney won voters with at least a four-year college degree in 14 of the 20 states, but he carried most non-college voters in just ten of them. But this time the class divide has widened to become the race's central fissure.

From the start, Trump has performed better in polling among Republicans without a college degree than among those who hold a four-year or post-graduate degree. Across the broad range of recent national and early state surveys, Trump consistently attracts about 40 percent of Republicans without a college degree—a remarkable number in a field this large. (The three latest Marist polls put him at 42 percent with them in Iowa, 41 percent in South Carolina and 36 percent in New Hampshire.) His performance among those with degrees is usually more modest: around 25 to 30 percent in most surveys.

Trump's success at connecting with the economic and cultural anxieties of blue-collar whites largely explains why he hasn't been damaged more by his disputes with groups that usually function as the gatekeepers for conservative support, from the Fox News Channel to National Review. Voters at Trump rallies are often quick to acknowledge he isn't a typical Republican, or a classic conservative. Yet they don't see his deviations from party orthodoxy as disqualifying because they view him as championing them against forces they view as threatening—from special interest influence in Washington to rapid demographic change. "I come out of a traditional Republican household," said Tom Cotton, a retired law enforcement officer from Grinnell, Iowa, who attended a Trump rally in Marshalltown last week. "And let's face it—he's not a traditional Republican. But I truly believe he will give it everything he's got to get things going again."

Trump's appeal with blue-collar Republicans also largely explains his success at remaining competitive with Cruz among evangelicals, despite the broad support the Texas senator has assembled from religious conservative leaders like Tony Perkins, the president of the Family Research Council. Figures provided by Marist from its new state surveys show that Cruz leads Trump by nearly two-to-one among college-educated evangelicals in Iowa, and runs even with the billionaire among them in South Carolina. But among evangelicals without a college degree, Marist found Trump thumping Cruz by 14 percentage points in both states.

Though Trump is showing strength across the GOP spectrum, one group consistently has expressed less enthusiasm about him: Republicans holding at least a four-year college degree. But those voters are now fragmented among a series of center-right choices, including Bush, Christie, Kasich, and Rubio as well as Cruz and Trump himself. That's especially true in New Hampshire, whose primary has often anointed the favorite of the party's college-educated "managerial" wing.

Trump's rivals all have different theories of how they would assemble a coalition against him. Cruz hopes to work in from the right; Christie, Bush, and Kasich to build out from the center; and Rubio to dip into all of the party's factions. Yet all are operating on the common belief—or maybe the hope—that Trump cannot expand his support enough to win if the race eventually becomes a one-on-one contest. "His Achilles' heel is his ceiling," said the senior strategist for another campaign. "He is continually the candidate not only with the highest very favorable rating, but the highest very unfavorable rating. He is utterly unacceptable to a very significant portion of the Republican electorate. And while he may be getting somewhat more acceptable to some of the donors, there is a huge portion of the Republican Party that will never ever support him. Ever. And the question now is: 'What is the size of that group?'"

An even more urgent question may be whether anyone can consolidate the forces resistant to Trump in time to stop the front-runner—especially if his broad new coalition propels him to an unprecedented sweep of the three critical states that kick off the GOP voting starting on Monday.

Janie Boschma contributed reporting.