This is a season of possibility for Republican politicians. Their party is poised to do well in November. Their Democratic opponents are stuck in neutral -- waiting for Hillary, praying for Obamacare. And thanks to a few strategically placed traffic cones, there is no front-runner for the GOP nomination in 2016, which means that more prominent Republicans than usual are dreaming the presidential dream.
Quite a few of them brought those dreams to the just-concluded Conservative Political Action Conference, jostling for the attention of activists, chasing cameras or being chased by them, trading compliments and subtle digs. A few, like the still-in-damage-control Chris Christie, were just there to pay their respects. But most were trying to ace CPAC's big audition, and prove that they could play the One True Conservative in the 2016 race.
The question is whether that role will actually exist. We're accustomed to a narrative of Republican politics that pits the Tea Party against the establishment, the right against the center right. But that has always been an oversimplification, and in a wide-open presidential campaign, it's likely to fit political reality more poorly than usual.
A better framework is suggested by Henry Olsen, writing in The National Interest, who argues that Republican presidential campaigns are usually defined by four factions rather than two. One faction is centrist (think John McCain's 2000 supporters, or Jon Huntsman's rather smaller 2012 support), one is moderately conservative (think the typical Mitt Romney or Bob Dole voter), one is socially conservative (think Mike Huckabee or Rick Santorum backers), and one is very conservative but more secular (think Gingrich voters last time, or Steve Forbes voters much further back).
The moderately conservative faction holds the balance of power, which is why the party usually flirts with ideologues but settles down with a safer, establishment-endorsed choice. But different campaigns take very different paths to this result.
In 1980, Ronald Reagan basically worked from the right to the center, consolidating secular and religious conservatives and then wooing enough moderate conservatives to win.
In 1996, Bob Dole relied on moderate conservatives to fend off a centrist (Lamar Alexander), a social conservative (Pat Buchanan) and a secular conservative (Forbes).
In 2000, George W. Bush used support from moderate conservatives and religious conservatives to defeat both McCain's centrist insurgency and Forbes' lesser challenge from the right.
In 2008, McCain combined his original centrist base with enough moderate conservatives to win the nomination - a trick Romney basically imitated in 2012.
Before the traffic problems in Fort Lee, Christie seemed poised to follow in Romney's and McCain's footsteps, uniting moderates and moderate conservatives and then trying to outlast whichever challengers emerged from the religious and nonreligious right.
But with Christie weakened, there are suddenly almost as many paths as there are plausible candidates.
The New Jersey governor could still follow McCain's 2008 path to victory, but he could also be marginalized, Huntsman-style, as a "centrists only" candidate - especially if a Scott Walker, a Paul Ryan or a Jeb Bush consolidated the support of moderate conservatives.
Then there's the potential Ted Cruz coalition, which could look like Reagan redux: secular conservatives plus religious conservatives to start, and then just enough moderate conservatives to win. But Cruz would need to consolidate the religious faction early, which is why he should be hoping that Huckabee and Santorum decide to forgo another run.
And then there is the fascinating case of Rand Paul, who has a potentially formidable base in two factions that don't usually ally - moderates who like his social libertarianism and secular conservatives who like his economic views.
Confused yet? Imagine being a Republican strategist or donor, trying to figure out where to place your bets. And I haven't even given you the Rick Perry and Bobby Jindal and John Kasich scenarios!
But let me conclude with one that seems a little more likely: a rerun of Bush's 2000 path, in which Marco Rubio wins by uniting religious and moderate conservatives.
Rubio had a tough 2013, thanks to his unsuccessful immigration push, and he lacks the ideologically committed support of a Paul or Cruz or Huckabee. But his domestic-policy forays (first on poverty, soon on taxes) have gotten smarter since the immigration debacle, and events in Venezuela and Crimea may be making his hawkish foreign policy vision more appealing to conservatives.
Moreover, as much as the party and the country have changed since the Bush era, the best way to unify the GOP is still to build bridges between religious conservatives and moderate conservatives - in effect, to seem relatable to Santorum voters while reassuring Romney voters. And Rubio, in affect and background and positioning, may be the right politician for that task.
Remember, I said "may." He's not the front-runner, because there is no front-runner. There are only factions waiting for their champion, and a party waiting for its biggest fight in years.
Ross Douthat is a columnist for The New York Times.
By ROSS DOUTHAT