A good horse race needs a front-runner, so an early media debate has broken out over who is the man to beat in the GOP race. Is it Jeb Bush, who leads in money and elite campaign staff, or is it Scott Walker who is outperforming Bush in many early polls?

The truth is that front-runner is a metaphor derived from the hasn't-been-popular-in-years sport of horse racing and lacks a well-defined meaning in the context of the (metaphorical) presidential horse race. A more useful way to think about it is this: Is Walker's combination of electability and ideological fit with his party good enough to beat Bush's elite connections and piles of money, or will his relative inexperience leave him falling on his face on the national stage. In other words, is he the Barack Obama of 2016 or the Rick Perry? Either are plausible. Only an actual campaign will let us know.

Walker as the Republican Obama

Jeb Bush's donor base, family name, and network of top tier political operatives make him formidable. But Scott Walker has a lot going for him:

Conservative credentials: Jeb Bush is a pretty conservative guy. But he has committed significant ideological deviations on Common Core and immigration. What's more, many conservative elites regard his brother's administration as excessively big spending. Walker, by contrast, is solid.

He's won in a blue state: The GOP often surprises liberals by settling on a nominee with a relatively moderate record. That's because electability matters to Republicans. But here's where Scott Walker shines. He's won three statewide elections in a state that went for Dukakis, Clinton, Clinton, Gore, Kerry, Obama, and Obama. And he did it recently. Jeb Bush won twice in a more conservative state and last ran in 2002. If you like Walker more on the issues, there's no particular reason to prefer Bush on electability.

Walker is acceptable: At this point, many Republican elites have rallied to Jeb Bush's standard. That speaks to the strength of his personal and family networks. But it doesn't speak to some kind of revulsion at Scott Walker. Nobody on the right has any big problems with Walker, and if he ends up as the nominee all the stakeholders will live with it. By contrast, many conservatives are genuinely angry at Bush over immigration.

Walker can raise money: Not as much money as Bush, to be sure, but enough to play. The Koch brothers are said to like him, there's a Midwestern donor network that's been very successful at taking control of the rust belt over this past decade, and hard-core supply-siders like him.

This adds up to a clear possibility of an Obama-like revolt by the mass party against a would-be dynasty, with immigration reform playing the role of the Iraq War. It's very plausible, and anyone who tells you that Bush's gigantic stack of Wall Street cash will be enough to win is mistaken.

Walker as 2016's Rick Perry

The problem with the Walker thesis is that you don't win elections on paper. If you did, Rick Perry would have wiped the floor with Mitt Romney in 2012. Oftentimes politicians struggle when they find that they have to speak about national issues to the aggressive national press corps.

Jeb Bush does not have this problem. Bush's rollout domestic speech struck me as slippery and dishonest, but it was a good speech. Similarly, his vacuous foreign policy speech was perfectly calibrated to where today's GOP stands.

By contrast, Scott Walker is boring people to tears when he's not fumbling questions on evolution or Barack Obama's religious faith.

None of this has killed Walker's chances by any means. But it hasn't helped him. And it illustrates what he'll have to overcome to win. He's got a great story to tell primary voters and party elites alike of a guy who ran and won in a blue state on a rigidly conservative platform, then beat back a recall challenge and then won re-election. Why settle for less? But the pitch as the best salesman for conservative policy only works if he actually looks like a good salesman when dealing with questions from the national press corps.

So far, he hasn't proved that he can shine on the big stage and Jeb has.

"We're going to have to wait and see what happens" is perhaps the most boring conclusion a pundit can possibly come to, but in this case it happens to be true. On paper, Jeb looks vulnerable and Walker looks like he has a great shot to exploit those vulnerabilities. But he hasn't done the work yet, and there's no way to know if he ever will until we watch him try.