We’ve known for months that the Republican Party is facing a difficult logistical challenge: with an enormous field of presidential candidates, how in the world are debates supposed to work?

As Rachel noted on the show last night, the plan is finally coming into focus. Rachel Kleinman reported for msnbc last night, for example, that the first debate will reportedly have (at least) 10 candidates.

According to information first reported by The Washington Post and confirmed by NBC News, Fox News, which will host the event Aug. 6 in Cleveland “will require participants to place in the top 10 in an average of the five most recent national polls in the run-up to the event,” noting that “[n]o GOP primary debate has ever featured more than 10 candidates.” Fox News has used similar criteria for past debates. Not to completely exclude those polling poorly, the right-leaning cable news channel will offer some air time to those who don’t make the cut.

With a GOP field that may reach 19 candidates , that means nearly half of the Republicans running will be on the outside looking in on debate night.

Also yesterday, Politico reported that CNN has adopted its own plan for its Sept. 16 debate: the top 10 candidates will have one debate, and there will be a separate debate for the other candidates who have at least 1% support in national polling.

It’s hard not to sympathize with debate organizers, who have a very difficult task, but these preliminary plans come with some complications.

1. National polling: Both Fox and CNN intend to rely on national polls, which are not always the best barometer for competitive candidates. Some will, for example, build support in Iowa and New Hampshire, long before they start to gain traction at the national level.

2. Incomplete polls: Because of the size of the field, some polls choose not to include some candidates. If you’re a pollster, do you keep Donald Trump’s name in the mix? How about Carly Fiorina? George Pataki? There’s no unanimity on this front, which clearly matters. If some pollsters don’t even include a longshot candidate’s name, they’ll have practically no opportunity to compete in a debate.

3. Ties? Fox said the first debate will be for the top 10 candidates, but if polling shows a tie between rivals, the network plans to err on the side of inclusiveness, so there may be more than 10. CNN, however, plans to use a series of tiebreakers to keep the total number of debate competitors at 10.

4. Which polls get included? As of this morning, going by RCP national averages , the following candidates would get to compete in the first debate: Jeb Bush, Scott Walker, Marco Rubio, Rand Paul, Mike Huckabee, Ted Cruz, Ben Carson, Chris Christie, Rick Perry, and Rick Santorum. But if we check in on the Huffington Post’s Pollster.com national averages , John Kasich would make the cut and Santorum wouldn’t. Relying on cold, hard data, in theory, makes this process easier, but in practice it’s not that easy. The networks are silent, at least at this point, on which polls will count and which won’t.

There are related considerations that organizers are probably on organizers’ minds. Carly Fiorina, for example, is the only woman in the GOP field, and excluding her from debates might raise questions about propriety. Donald Trump, meanwhile, says he expects to be included because his participation would improve ratings, which may well be true.