Liberals often say that Fox News is the house organ of the Republican Party, but in the 2016 election, the network is becoming something more: a kind of stern boss, setting the agenda, plotting the group's course, and weeding out the weak performers. As powerful as the network has been within the conservative movement, the 2016 election has given it the opportunity to increase its influence even further.

That's partly because someone has to organize the chaos that is the Republican primary race, and no one's better positioned to do it. But before we get into it, let's step back for a moment.

We're in a contradictory time in American politics. On one hand, partisanship has barely ever been higher. Liberal Republicans and conservative Democrats have been almost completely driven from Congress. Crossover voting has declined almost to nothing; in 2012, for instance, 92 percent of Democrats voted for Barack Obama, while 93 percent of Republicans voted for Mitt Romney.

Yet on the other hand, the parties as institutions have grown weak. With the newly expansive campaign finance landscape engineered by the Supreme Court, the big money is pouring not to the DNC and RNC but to super PACs, 501(c)(4)s, and other vehicles for influencing the outcome of campaigns. Where just a short time ago these outside groups were content to just buy a bunch of ad time, they're increasingly focused on many of the things the parties have traditionally done, like the ground organizing that's so critical to victory.

And even if the RNC were stronger, its stance of neutrality would prevent it from doing what may be necessary to bring order to the primaries. So Fox is stepping in. This week the network announced that for the first Republican debate in August, they're going to limit the participants to 10 — despite the fact that the number of actual candidates (official or otherwise) could be 15 or even 20. If you haven't scored high enough in a set of recent polls Fox chooses, then you're out of luck.

At the moment, the top 10 in polls includes people like Ben Carson and Donald Trump, but wouldn't include Bobby Jindal, Lindsey Graham, or Carly Fiorina. It wouldn't exactly be good for the party's outreach to women if the one woman in the race was shut out of the first debate, but Fox has decided that 10 candidates is more than enough.

And make no mistake, being excluded from that first debate could be a major blow to a candidate's campaign. Media attention, money, and poll results influence each other in a constant cycle during the primary. If a candidate isn't on stage with the big boys at the first major gathering, the news media may decide he (or she) isn't worth wasting time on, voters will subsequently focus on only the candidates they think have a chance to win, and the candidate will then have an even harder time raising money and will languish in the low single digits. Which means they could be excluded from the next debate, and the cycle will spin them downward to the point where continuing to run seems pointless.

And that's not the only way Fox is trying to organize this race. Don't forget that the nightmare Jeb Bush just went through trying to explain whether he would have invaded Iraq started when he got asked the question by Fox's Megyn Kelly. When Marco Rubio went on Fox News Sunday soon after, Chris Wallace went after him on the same question like a prosecutor questioning a murder suspect. There won't be many more softball interviews for GOP candidates on Fox: Now the network is testing, probing, and challenging them to make sure they're on their game. It's weeding out those who don't measure up.

Fox News chief Roger Ailes' genius has always been in his ability to balance Fox's twin goals: making money and serving the interests of the Republican Party. But at a time like this, the latter goal becomes more complicated to achieve than when Republicans are just fighting with Democrats. And some Republicans who just a few months ago could expect nothing but hugs and applause from the network now aren't getting such friendly treatment.

Once there's a GOP nominee, he'll be praised and defended on Fox News like he was the second coming. But until then, Fox is going to work to find the strongest candidate and get rid of the rest. Because if they don't do it, nobody else can.