Aboard the campaign plane late in the 2012 election, Jeb Bush (L) and Mitt Romney. Sen. Marco Rubio (R-Fla.) sits across from them.  (Photo by Melina Mara/The Washington Post)

Former Florida governor Jeb Bush (R) has kind-of, sort-of started the 2016 GOP primary, and he does so as something of a front-runner.

But only in the loosest sense of the word.

A new Washington Post-ABC News poll of Republicans and Republican-leaning independents released Tuesday shows Bush running first in a GOP field without Mitt Romney, though not leading by a statistically significant margin. He gets 15 percent, compared to 11 percent for both Sen. Rand Paul (R-Ky.) and Rep. Paul Ryan (R-Wis.).

In a field with Romney, Romney leads Bush 20-10 percent, with Paul at 9 percent and Ryan at 8 percent.

Here's how that looks:

Whenever someone complains that polling this far out doesn't matter, we sigh just a little. Hillary Clinton's poll standing, after all, is pretty indicative that she's the favorite for the Democratic nomination. That's an extreme example, but you get the idea.

In the GOP field, though, this is all just guesswork. And you could make a pretty strong argument that Romney and Bush only lead because they have the most familiar names.

And in that sense, their standings are kind of underwhelming. Romney, after all, was the party's 2012 nominee and remains a pretty active politician, and Bush's showing in a race with or without Romney is pretty pedestrian, given his political lineage and reputation as a serious politician. He's only a few points ahead of Rick Perry and Ben Carson, after all.

So to call either Romney or Bush a front-runner at this point isn't really saying much. It's technically true, but this field of candidates is so jumbled right now that things will be quite fluid and highly dependent one who actually runs.

The biggest question from here on out is not so much who leads in the polls, but who runs. If Marco Rubio, Chris Christie and Romney all run, that cuts into Bush's chances, because he draws from the same pools of supporters and donors. That's not so much the case with Carson, Mike Huckabee, Rand Paul and Ted Cruz.

This poll tested 14 candidates. Not all 14 will run, but the combination of who does run will go a long way toward determining who the front-runners really are.

We won't really know for a few months -- and possibly much longer than that.

The Post-ABC poll was conducted by telephone Dec. 11 to Dec. 14, among a random national sample of 1,000 adults. The poll had a margin of error of five percentage points for the sample of 458 Republicans and independents who lean Republican.