Republican presidential candidate Donald Trump addresses supporters during a political rally at the Phoenix Convention Center on July 11, 2015. Trump spoke about illegal immigration and other topics in front of an estimated crowd of 4,200.Charlie Leight AFP/Getty

This article is from the archive of our partner National Journal

The paradox of Donald Trump's bombastic presidential campaign is that his rise may ultimately benefit the rival he has attacked most vociferously.

With his rambling and belligerent speech in Phoenix last Saturday, Trump signaled again that on the sprawling list of targets that inspire his antagonism, former Florida Gov. Jeb Bush ranks near the bulls-eye. "If you people go with Bush," Trump insisted flatly during the speech, "you are going to lose."

And yet, while he is creating some risks for the nominal front-runner, many Republican analysts predict that Trump eventually could prove more asset than obstacle to Bush's bid for the party nomination. "If you were a total evil-conspiracy theorist, you'd think the Trilateral Commission got Trump to run because "... it helps Jeb more than anybody," says longtime Republican strategist David Carney.

The surge of interest in Trump could threaten Bush in one important respect: by radicalizing opinion within the party on immigration issues where Bush has taken a relatively moderate position.

But Trump's ascent could inadvertently help Bush, both by providing him a foil in the immigration debate, and also by dividing the populist conservative voters who are least likely to ever support an establishment favorite like the former Florida governor.

That dynamic could especially threaten Wisconsin Gov. Scott Walker, who formally announced his candidacy Monday and has taken a series of steps—including a hard line on both undocumented and legal immigration—to court the same disaffected voters now flocking to Trump in polls.

Trump's most obvious threat to Bush is intensifying the spotlight on immigration, an issue where Bush already faces formidable resistance from the GOP's most conservative elements.

Even before Trump raised the temperature with his attacks on Mexico, immigration had emerged as a major dividing line in the 2016 GOP race. Almost all of the Republican contenders have rejected any legal status for the estimated 11 million undocumented immigrants in the U.S., which Bush has consistently supported (although he has wavered on whether he would also accept citizenship, as opposed to permanent legal status, for them).

In addition, three contenders—Walker, former Sen. Rick Santorum of Pennsylvania, and former Arkansas Gov. Mike Huckabee—have suggested a reduction as well in legal immigration, which Bush has also rejected. Now, Trump's vitriolic attacks on Mexico have galvanized so much attention that they appear likely to dominate the first GOP presidential debate on Fox News Channel in August.

Polling conducted this spring in Iowa, New Hampshire, and South Carolina, sites of the critical three early GOP contests, found that a majority of likely Republican voters in each state supported either legal status or full-scale citizenship for the undocumented. In the surveys conducted by Burning Glass Consulting, founded by three women with a long pedigree in GOP politics, only 29 percent of likely GOP primary voters in Iowa, 34 percent in New Hampshire, and 37 percent in South Carolina said the undocumented should be denied any legal status.

But Katie Packer Gage, the cofounder of Burning Glass, and the deputy campaign manager for Mitt Romney in 2012, says those attitudes could buckle under a sustained campaign argument about immigration. "I don't think we want to have the whole discussion be on immigration," she says. "When you look at our poll in the primary states, the majority is for a pathway [to citizenship or legal status], but it's more like they would accept a pathway. It's not like they are anxious for it."

Indeed other surveys show a substantial strain of anxiety about immigration—both undocumented and legal—running through the GOP coalition, particularly among the party's substantial blue-collar and older constituencies. In one national Pew Research Center poll, nearly half of Republicans older than 50 and those without a four-year college degree opposed any legal status for the undocumented. Meanwhile, more than three-fifths of each group said legal immigrants were more a burden than a benefit to American society. On each issue, considerably fewer younger and college-educated Republicans expressed those conservative views.

Although Trump broadly praised legal immigration in his Saturday speech, most analysts believe Trump's support is likely to flow most from the blue-collar and populist Republican voters who respond not only to his attacks on undocumented immigrants and free trade, but also to his blunt nonpolitician style. "They tend to be people who like the idea that he's not a politician: They say this is a guy who 'says it like it is' and he doesn't care what people think." Gage notes. "They like that he is a very successful businessman." Trump sent a clear signal to those voters on Saturday when he reprised a phrase from the Richard Nixon era that referred to overlooked middle-class white voters and insisted: "The silent majority is back, and we're going to take the country back."

Trump's potential appeal to voters in the party's populist wing is what could tilt his impact on Bush from threat to asset. Polls generally show Bush running best among the party's "managerial" wing of college-educated, moderate, and upscale voters. That means if Trump can sustain his support—which many Republican analysts question—he is likely to be strongest among the voters where Bush is weakest. And to the extent Trump attracts those voters, he denies them to more-conventional Bush rivals like Walker or Sen. Marco Rubio of Florida.

Many GOP analysts agree that Bush will benefit if voters alienated from him gravitate to Trump, who probably faces a lower ceiling of total support, than to Walker or Rubio, who have the potential to build a broader and more potent coalition. Combining results from the past three NBC/Wall Street Journal national surveys, just 27 percent of GOP primary voters said they would consider voting for Trump, far fewer than indicated they could back Bush, Walker, or Rubio.

Janie Boschma

Trump creates even more immediate problems for second-tier candidates such as Sen. Ted Cruz of Texas, former Texas Gov. Rick Perry, Huckabee, and Santorum, who have all targeted a similar group of blue-collar and conservative voters. "It just takes the energy out of the room, and it's going to be harder for a person not in first place to break through," says Carney, a top Perry strategist in 2012.

Still, Walker may be the candidate with the most at risk from Trump's ascent. Longtime New Hampshire GOP activist Tom Rath, who is unaffiliated in 2016, says that in the state's critical primary next February, Trump "really hurts Walker, because Walker's path to winning the nomination is to do really well in Iowa and then come in here and become the dominant ideological conservative coming out of here, and parlay those two things into a good showing in South Carolina." But, Rath adds, "Walker only can do that if the Right doesn't splinter."

The latest CNN/WMUR/University of New Hampshire poll conducted there last month underscores Rath's point. Across several key dimensions, the voters who express the most favorable opinions of Trump represent the opposite of those most favorable toward Bush. While Bush's favorability rating is highest among voters with a postgraduate degree (57 percent favorable), Trump does best (52 percent favorable) among those with a high-school degree or less. While Bush performs best among those opposed to the tea-party movement (57 percent favorable), Trump does best with those who support it (47 percent). In New Hampshire, Trump is more popular with men (41 percent favorable) than women (33 percent); Bush is more popular with women (54 percent favorable) than men (47 percent). Trump is more popular with conservatives (42 percent favorable) than moderates (33 percent); Bush is more popular with moderates (56 percent favorable) than conservatives (50 percent).

Tellingly, on almost all of these measures, Walker's profile is closer to Trump's than to Bush's. Like Trump, Walker is much stronger with tea-party supporters (61 percent favorable) than those who oppose the movement (27 percent). Again like Trump, Walker is much more popular with men than women and also more popular with conservatives than moderates. On education, Walker straddles the divide between Bush and Trump (Walker shows the most support among those with a high school degree or less or those with a postgraduate education).

All of these findings reinforce Rath's conclusion that any votes Trump wins in New Hampshire are likely to come "right out of Walker's pocket and therefore the Right doesn't coalesce and it makes the winner of the primary, which tends to be the center-right [candidate], really the winner here, as opposed to muffling or muddling the message."

Trump could benefit Bush in one other way: By expressing suspicion of immigrants in such unvarnished and incendiary language, the billionaire could provide the former Florida governor a foil to make his own views appear more mainstream, not only in the primary but also in the general election if he gets that far. Carney says that while "it's hard to predict" how the business executive's explosive rhetoric could shift the balance of opinion within the GOP on immigration, by framing the debate as such a binary choice with Bush, Trump may inadvertently encourage more moderate voters to align with his rival, rather than consider another center-right candidate in the field such as New Jersey Gov. Chris Christie.

"Bush is going to get attacked; front-runners always get attacked, they know that," Carney says. Trump is "really the other guys' problem: everyone sitting in a [campaign office] in Kentucky and Austin and Baton Rouge and Milwaukee, figuring out 'what the hell are we going to do about this?'"

This article is from the archive of our partner National Journal.

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