This article is from the archive of our partner National Journal

No Republican presidential hopeful since George W. Bush in 2000 has generated widespread support across the party's class and cultural divides. The next GOP nominee may be the candidate who most closely matches his success.

The Republican presidential primary electorate now divides about evenly between two factions. The GOP's "managerial" wing consists of voters who are generally more affluent, better educated, more secular, and somewhat less ideological. The party's "populist" wing draws on the overlapping circles of evangelical Christians, blue-collar voters, and the most committed conservative believers.

As a Harvard MBA who memorably identified "Jesus" as his favorite philosopher, Bush largely transcended those divides. In the decisive 2000 primaries, Bush consistently beat John McCain, his principal rival, among both college and non-college voters. Bush dominated among voters who identified as religious conservatives and essentially matched McCain with those who did not.

By contrast, the nominees in 2008 and 2012, McCain and Mitt Romney, relied predominantly on managers to compensate for substantial resistance from the populists. Both men made major primary-season concessions to conservative activists (particularly on immigration) that damaged their general election appeal. Yet both still struggled among hard-core conservatives. Ultimately, McCain and Romney each followed a winning formula of 50/30: both attracted almost exactly 50 percent of non-evangelical voters and around 30 percent of evangelicals in Republican primaries, according to a cumulative analysis of exit polls by ABC News' Gary Langer.

One reason McCain and Romney overcame their limitations is they faced rivals with even narrower appeal. Mike Huckabee in 2008 and Rick Santorum in 2012 emerged as the principal alternative to the front-runner through the same route: winning the Iowa caucus by consolidating support from evangelical Christians (who cast most votes there each time.) But neither could advance enough beyond that beachhead. Through all the primaries, Santorum cumulatively won fewer than one-in-five non-evangelicals, and Huckabee only one-in-ten, Langer found. "They allowed themselves to be labeled as 'the candidate of the social conservatives,'" says Jamie Johnson, an Iowa GOP central committee member who served as Santorum's state coalitions director. So while McCain and Romney did not display as much breadth as Bush in 2000, they won partly by showing better balance than their rivals.

Can any of the 2016 candidates truly span the party—especially without taking positions that hurt their general election prospects? Although Chris Christie also could compete, Jeb Bush seems most likely to fill the McCain/Romney "managerial" slot. NBC/Marist polls released this week showed Bush already leading or tied with moderates in Iowa and South Carolina and running a close second (to Christie) among them in New Hampshire. Bush's strong social conservative record as Florida governor should open doors with evangelical Christians. But his support for immigration reform and especially the Common Core educational standards antagonizes many of their leaders. While the NBC/Marist surveys did not find lockstep rank-and-file evangelical opposition to common core or immigration reform, that resistance could harden in a campaign. Replicating the 50/30 formula that worked for McCain and Romney might be this Bush's best chance.

Kentucky Sen. Rand Paul has an eclectic appeal that could transcend some divides. But he faces a different barrier. With his "libertarian-ish" agenda and informal manner, Paul should run well with younger Republicans. His problem is that voters over 50 cast more than 60 percent of the 2012 primary votes. And many older Republicans may view Paul more as a provocative college professor than a potential commander-in-chief. In each of the NBC/Marist polls, Paul ran at least twice as well among Republicans under 45 than those who are older.

Huckabee, Santorum, surgeon Ben Carson, and Sen. Ted Cruz will duel for evangelical support in Iowa. Johnson thinks Cruz could assemble a broad coalition of conservatives, but other analysts are skeptical he (or the other three) can grow much past the party's ideological vanguard.

Florida Sen. Marco Rubio might appeal widely but is struggling in Bush's shadow. That leaves Wisconsin Gov. Scott Walker as the contender with potentially the broadest audience. The son of a Baptist minister who has dueled with public employee unions as governor, Walker "has an ability to bridge a couple of the lanes," says Scott Reed, Bob Dole's 1996 campaign manager. In all three NBC/Marist polls, Walker's support was virtually equal among evangelical and non-evangelical Republicans. Well positioned for breadth, his challenge will be depth—pulling deeply enough from either managers or populists to actually win the key contests. "When you are drawing from multiple camps "¦ you have to be strong enough that it's not a formula for second place," says former Iowa GOP chairman Brian Kennedy.

Historically, Iowa favors populists and New Hampshire prefers managers. If a manager like Bush wins Iowa because conservatives splinter, he would become very hard to beat. Alternately, if Iowa again elevates a populist winner who struggles to expand beyond evangelicals (such as Cruz), it would benefit the managers' favorite. But if Iowa gives its boost to Walker, his potential to cross the party's central divides could make him much more formidable than the past two caucus winners.

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

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