The billionaire Koch brothers' plans for 2016 have dominated political headlines this week.

On Monday afternoon, it looked like the brothers were endorsing Scott Walker. By Monday evening, David Koch had declared his neutrality. Twenty-four hours later, Charles Koch explained there were five GOP contenders in the mix for the brothers' backing. And on Wednesday, Politico's Ken Vogel obtained a memo outlining the brothers' spending plans for 2016.

What's the upshot of all this? Overall, it's clear that the Kochs are being bolder than ever in their attempts to mold the political process to their will. They're trying to raise an astonishing amount of money to ensure Republican victories in 2016 — and they're holding out their potential endorsement, and the cash that could come with it, to help ensure GOP contenders back the policies they want.

While the Kochs' influence is important, it shouldn't be oversimplified. Their decision not to endorse right now seems to be an acknowledgement that they can't hand-pick one candidate in a wide-open field. Instead, the brothers are trying to keep their options open, hoping not to lose leverage over whoever becomes the eventual nominee.

However, in a sense, they don't need to be too picky. Because on the economic issues they care about most, the key GOP contenders are already very conservative. The Republican Party, overall, has already moved quite far in the Kochs' direction.

The Kochs are making their boldest play ever for political influence

What the Kochs are trying to do in 2016 is unprecedented. Their political organization hopes to raise an astounding $889 million before the election. About a third of that will be explicitly devoted to electoral politics, Charles Koch told USA Today's Fredreka Schouten. This potentially leaves room for a good deal more to be spent on "issue ads" — which can be used to attack politicians without technically counting as electoral spending, according to the FEC.

While the bulk of the Koch network's electoral spending will be used against Democrats, Charles Koch is now saying the brothers might intervene in the GOP's presidential primary, too — which they haven't done before. Indeed, the Kochs are magnanimously giving certain candidates a chance to "audition" for their support, as Politico's Mike Allen put it, at various events attended by the wealthy donors who contribute to their network.

And even though only three significant candidates are officially in the GOP race, and the total number is expected to rise to 15 or even higher, the Kochs have already publicly winnowed down the field to five: Scott Walker, Jeb Bush, Marco Rubio, Ted Cruz, and Rand Paul. "Those are the ones we have talked to the most and who seem to be the possible leaders," Charles Koch told Schouten.

Most of these candidates have, accordingly, kissed the brothers' rings. At a Koch event in January, Ted Cruz said the brothers "have stood up for free-market principles and endured vilification with equanimity and grace." At the same event, Marco Rubio, when asked whether super-wealthy political donors have too much influence on politics, argued that "spending money on campaigns is a form of political speech." And Rand Paul wrote in Time last week that the Kochs "have always stood for freedom, equality and opportunity."

But the Kochs can't hand-pick the GOP nominee — and aren't trying to

As important as the Kochs surely are in shaping politics today, it's important not to get carried away. They aren't trying to singlehandedly pick the GOP's nominee — probably because they expect they wouldn't be able to.

That's evident from an article by Ken Vogel — one of the best-sourced reporters covering the Kochs — that leaves the distinct impression that the brothers' tough talk of playing in the primaries may be a bit of a bluff.

According to Vogel, the Koch network won't make a decision about whether to intervene in the primaries until "early next year." This suggests that, rather than sticking their necks out and endorsing, the Kochs would prefer to wait for voters in early primary and caucus states to winnow down the number of candidates.

And that makes sense. In such a crowded field, the Kochs can't claim to know, so far in advance, which candidates will be most likely to win voter support and which will flame out. A premature endorsement of, say, Walker could well be followed by the candidate utterly failing to impress on the trail, and going nowhere.

Indeed, Vogel's sources "caution" him further, saying that a primary intervention "likely would only happen if the final field pitted a candidate seen as aligned with the Koch’s small-government ideology ... against one considered anathema to it."

The Kochs' ambitions for an unprecedented pro-GOP general election effort also seem incompatible with playing favorites in the primary. The Kochs' political organization is funded not only by the brothers, but by many other wealthy donors they've recruited — about 450 in total, according to Schouten. Many of these donors will have their own favorite candidates in the primary. Already, hedge fund magnate Robert Mercer is funding Ted Cruz, while wealthy donor Foster Friess plans to fund a repeat Rick Santorum bid. These donors won't want their money going to fund a candidate they dislike.

It's also noteworthy that Charles Koch's shortlist of contenders contains all three of the people generally viewed as most likely to win the nomination — Jeb Bush, Scott Walker, and Marco Rubio. The Kochs aren't taking much of a risk by keeping every contender the insiders believe to be plausible in the mix for their endorsement.

None of the likely candidates are a perfect fit for the Kochs

Indeed, if the Kochs wanted to be truly picky, they could find a lot to dislike about each of the five candidates on their list.

Jeb Bush has been heavily fundraising from the DC business lobbyist establishment that the Kochs say exemplifies cronyism. He's also supported the Common Core standards that Koch-funded groups like Americans for Prosperity have been crusading against for years.

Scott Walker, meanwhile, has recently moved far to the right on immigration — an issue on which the Kochs are closer to Jeb Bush's support for reform. Walker also stands out among the GOP field "as distinctly unfriendly toward criminal justice reform," another major cause of the Kochs, Leon Neyfakh writes at Slate.

And then there's Marco Rubio, whose interventionist views on foreign policy should raise an eyebrow among the Kochs, who "generally disapprove of foreign military interventions and were no fans of the Iraq war," according to their biographer Daniel Schulman. (Reason's Matt Welch called Rubio "the anti-Rand Paul on foreign policy.")

Meanwhile, the other two candidates on the Kochs' short list — Ted Cruz and Rand Paul — appear to be closer to the brothers' views on economic and foreign policy. But the Kochs definitely want the GOP candidate to win in 2016, and there are electability concerns for both Cruz and Paul. Paul in particular failed to impress at a Koch event in January, according to Vogel and his colleague Tarini Parti, who reported that in an informal straw poll of 100 donors in attendance, Paul finished last among several contenders.

But the GOP's rightward drift on economic issues is unchallenged — for now

Viewed through another lens, though, the fact that the top three insider contenders for the GOP nomination are all compatible with the Kochs' far-right economic views is a tremendous victory for them.

The Kochs have longed seem to prioritize economic issues — shrinking government, slashing entitlement spending, cutting taxes, and reducing regulations — far above other matters. And it hasn't been too long since the big-spending, Medicare-expanding George W. Bush administration drew their ire.

The prospect of the GOP nominee pledging a major entitlement expansion seems unimaginable now. Instead, the entire party has backed Paul Ryan's plans to overhaul Medicare, to reduce government spending on the program. More broadly, this year's contest features the spectacle of every major hopeful competing to trash the Export-Import Bank — a longtime target of the Kochs, who view the agency as exemplifying government interference in the free market. Support for action on climate change, for Obamacare, or for campaign finance reform are all anathema for the vast majority of the expected presidential field — as they are for the GOP in general.

So the GOP contenders generally considered to be most formidable look quite appealing to the Kochs. Walker fought public unions in Wisconsin, Rubio supports slashing taxes and spending, and even Jeb Bush is well to the right of his brother on economics if one looks at his record in Florida.

The true test for the brothers would come if a candidate who challenges some of this new anti-spending GOP dogma gains steam. Mike Huckabee has been criticized by fiscal conservatives for increasing taxes and spending during his Arkansas governorship. Lindsey Graham has backed the Export-Import Bank — and, perhaps more significantly to the Kochs, has backed action on climate change. And John Kasich signed on to Obamacare's Medicaid expansion.

None of these potential candidates look like they're about to catch on right now. But if one of them rises in the polls, or wins an early state primary or caucus, expect the Kochs to have something to say about it.