WASHINGTON -- As they strategize to spend as much as $400 million to defeat President Barack Obama and help Republicans win control of Congress, the billionaire brothers David and Charles Koch and an allied network of wealthy conservatives are looking to funnel tens of millions into conservative-leaning groups for television ads and get-out-the-vote drives.

Three GOP fundraisers familiar with the plans of the billionaire Koch brothers and their rich friends told The Huffington Post that their donor network is expected to funnel this year tens of millions into conservative groups, including the National Rifle Association, Grover Norquist's Americans for Tax Reform, the National Right to Life Committee, Ralph Reed’s Faith and Freedom Coalition, the 60 Plus Association and the American Future Fund. By spreading their wealth throughout the conservative ecosystem, the Kochs can exploit trusted brands with passionate followings that reach beyond the Tea Party base. These three sources all requested anonymity since they are not authorized to speak about the Koch donor network's plans.

The billionaire brothers, working with the Koch-founded Americans for Prosperity, aim to enlist these groups' grassroots networks to mount a national get-out-the-vote drive and ad blitz that could prove crucial to GOP fortunes in battleground states.

While they have not always worked in sync, representatives of the Kochs have been meeting regularly this year with leaders of other big GOP allies, notably the Karl Rove-backed super PAC American Crossroads and the U.S. Chamber of Commerce. These elite planning meetings involving Koch representatives take place in addition to larger meetings hosted periodically by American Crossroads with a dozen or so GOP groups since the 2010 midterm elections.

If the Koch-backed efforts hit their fundraising goals this year, they will rival -- and perhaps surpass -- the target of $300 million that American Crossroads and its affiliated nonprofit Crossroads GPS have set for their electoral drives. The two Crossroads groups raised $71 million in 2010 after being set up by GOP strategists Rove and Ed Gillespie in the wake of high court rulings that opened the floodgates for unlimited spending by corporations, individuals and unions on advertising and other electoral tools that directly advocate for candidates.

The $400 million fundraising target of the Kochs and their mega-donor associates was first reported by Politico on Wednesday and confirmed by the three GOP fundraisers who spoke to HuffPost over the past several weeks.

To rev up the Koch-led fundraising machinery, a few dozen rich conservatives and consultants from Wall Street, Las Vegas, California and other locales flew into Palm Beach one Friday early this spring for a conference organized by the billionaire brothers. The event featured detailed election strategy talks by, among others, Tim Phillips, the president of the Koch-backed nonprofit Americans for Prosperity; since late last year the group has announced about $15 million in TV ad buys blasting White House policies on energy and other issues.

Another prominent guest in Palm Beach this spring was Ken Cuccinelli, Virginia's attorney general. A major player in court challenges to the constitutionality of President Obama's health care reforms, Cuccinelli served as a featured speaker.

The Florida event took place at the ritzy PGA National Resort & Spa and included a dinner at David Koch's Palm Beach mansion, according to two of the three fundraisers who spoke to The Huffington Post and participated in the day. The third fundraiser heard details of the Koch electoral spending plans from one of the brothers. The Koch brothers themselves are expected to chip in at least $60 million and perhaps as much as $100 million toward the $400 million goal, say these three fundraisers.

The Kochs, who have long hosted twice-a-year conferences drawing scores of wealthy conservatives -- typically in January and the summer -- have worked hard to maintain secrecy about their contributions and donations by their allies. The Palm Beach event served as an extra fundraising and strategy session this year.

A Charles Koch speech at a Koch-sponsored conference in the summer of 2011 identified more than two dozen $1 million-plus donors over a year's time. Charles Koch cited, among others, mutual fund tycoon Foster Friess, Amway cofounder Richard DeVos and Oklahoma oil and gas mogul Harold Hamm as patrons who gave at least $1 million.

Two other $1 million donors mentioned by Charles Koch also had a presence in Palm Beach: Paul Singer, who runs the giant hedge fund Elliott Management, attended the spring event, along with a consultant for Charles Schwab of the eponymous investment firm.

THE GROUND WAR AND AIRTIME STRATEGY

A hefty share of the donor network's money will be directed to 10 battleground states in the presidential race, including Florida, Ohio and Virginia. These states and a few others also have high-stakes Senate races under way and the GOP is hoping to win enough seats to regain the majority.

The Koch donor network's strategy to funnel large sums to powerful allies mirrors what Crossroads GPS has already done by shelling out millions to allies such as the NRA, Americans for Tax Reform, the National Right to Life Committee, according to these three GOP fundraisers. In April, Crossroads GPS disclosed that it gave millions to conservative outfits in its IRS filing of required 990 tax forms, covering its first 18 months of operations. Neither Crossroads GPS nor the Koch favorite Americans for Prosperity are required to disclose the identity of their donors because of their nonprofit tax status.

The NRA’s electoral efforts this year seem to offer an example of how the Kochs' strategy can work, according to the three GOP fundraisers. The NRA, they say, has already received a hefty cash infusion from the Koch donor network this year, enabling the 4 million-member pro-gun behemoth to expand voter registration and get-out-the vote drives.

The NRA hired about two dozen “campaign field representatives” to coordinate NRA ground operations and voter registration work in a dozen battleground states, including Florida, Ohio and Virginia, Chris Cox, the NRA’s top lobbyist told me for a Center for Public Integrity article. The drive will target “gun shows and retailers” and includes a six-figure TV ad blitz that launched in February, Cox said.

This is all part of the NRA's multimillion dollar “Trigger the Vote” registration drive, expected to be its largest ever, Cox said. “This election is going to be won on the ground,” Cox stressed, adding that millions of gun owners are not registered to vote. Most of the NRA voter registration campaign is being funded through its Freedom Action Foundation, a nonprofit not required to disclose donors.

Cox declined to discuss large donors but said that the foundation is mostly financed by small donors; corporate filings have revealed, however, that Texas energy magnate Clayton Williams donated $1 million in 2010. Williams told a Houston luncheon last summer that he would pony up another million for the foundation again this election year, according to two luncheon attendees.

The increased emphasis by the Kochs and their allied super donors on underwriting ground operations could prove crucial in battleground states where Democrats have often had an edge in getting out the vote because of well-funded labor efforts. The AFL-CIO and other unions, for example, plan to spend $400 million on federal, state and local races this year. But Democratic super PACs and nonprofits might raise only $100 million to $150 million this election, say Democratic operatives, and are lagging behind their GOP rivals in raising money.

In the near term, the Koch brothers' network, along with Americans for Prosperity and its allied foundation, is flexing its financial muscle to help Wisconsin Gov. Scott Walker win a June 5 recall election. David Koch sees a hero in Walker, who galvanized liberal opposition with his anti-union policies and cuts to public services.

Several months ago, Koch told the Palm Beach Post that Scott Walker is “an impressive guy and very courageous” in taking on public unions. Americans for Prosperity’s foundation spent $700,000 earlier this year on ads defending Walker’s campaign against collective-bargaining “abuses.” A Wisconsin Americans for Prosperity chapter launched a 10-city bus tour late last month that it bills simply as educational.

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