It seems hard to fathom now, but the Republican establishment once viewed the Kochs as a threat. In the late 1970s, National Review — now a reliable defender of the brothers — devoted a series of articles to eviscerating the libertarian movement and its angel investor, Charles Koch, whom the magazine described as "a man whose wealth and devotion to privacy are straight out of the Howard Hughes legend."

Now the Koch brothers, thanks to their sprawling political and fundraising network, are the toast of the GOP, while Democrats have taken up the cause of demonizing them, even placing them at the center of their midterm election strategy. Senate Majority Leader Harry Reid (D-Nev.) recently suggested that Senate Republicans should "wear Koch insignias to denote their sponsorship." The Democratic Senatorial Campaign Committee, meanwhile, has rolled out a Web site proclaiming that the "GOP is addicted to Koch."

But their fiercest critics on the left may be surprised to learn that the Kochs actually share a host of views with them, particularly on social issues (though emphatically not on economic ones). And now that the brothers wield significant influence within the Republican Party, they have an opportunity to push it closer to the center on issues that have caused members of many key voting blocs — women, Latinos, youth — to shun the GOP.

For a party undergoing an identity crisis, a Koch-style makeover may not be such a bad thing.

The brothers have achieved political notoriety for bankrolling the tea party movement, leading the charge against Obama­care , stoking skepticism about climate change and carpet-bombing the airwaves with ads targeting vulnerable Democratic lawmakers via their advocacy group Americans for Prosperity. But lesser known are the issues on which they are at odds with the conservative mainstream.

The Kochs generally disapprove of foreign military interventions and were no fans of the Iraq war. As a young man, Charles strongly opposed the Vietnam War, even though this position was highly unpopular in his home town of Wichita, headquarters of military contractors such as Beech and Cessna that supplied the war effort. His activism so angered the leadership of the conservative John Birch Society, which his father had played a role in founding and where Charles was a member, that he was forced to part ways with the group in the late 1960s after placing an antiwar ad in the local newspaper.

David has criticized U.S. drug policy and victimless-crime laws. "I have friends who smoke pot. I know many homosexuals. It's ridiculous to treat them as criminals," he said in 1980. He supports same-sex marriage and abortion rights — positions that risk his standing in the GOP. Charles seemingly shares these views. "What a spectacle it is for the same people who preach freedom in voluntary economic activities to call for the full force of the law against voluntary sexual or other personal activities!" he wrote in his 1978 jeremiad. "What else can the public conclude but that the free-market rhetoric is a sham — that business only cares about freedom for itself, and doesn't give a damn about freedom for the individual?"

The Kochs have largely remained quiet on these issues in recent decades, but David made headlines at the 2012 Republican National Convention in Tampa, when he told Politico, "I believe in gay marriage." His remark came just days after the GOP had officially hammered out a platform calling for a federal ban on gay marriage.

The libertarian movement, in which Charles and David Koch were leading figures, attempted to forge an alliance with the political left by highlighting the issues on which they could agree, such as robust civil liberties, a non-interventionist foreign policy, reproductive rights and the elimination of corporate subsides. It sought to demolish "the two-party monopoly," as David put it when he accepted the Libertarian Party's vice-presidential nomination in 1979. But the fractious movement imploded in the wake of the 1980 election, after David and his running mate claimed 1 percent of the popular vote but came under fire from within the libertarian ranks for diluting the movement's radical agenda on the campaign trail. (They had, for instance, committed the heresy of failing to call for the full eradication of the income tax.)

The Kochs ultimately abandoned the Libertarian Party, though not its core beliefs, once the futility of challenging the two-party system became clear. Thus began their three-decade climb from libertarian gadflies to Republican power brokers. The question now is what they will do with their newly acquired clout within the GOP.

The brothers have focused their advocacy largely on economic issues, such as blocking passage of 2009's climate bill and pushing for steep decreases in state and federal spending, but there have been subtle signs that they are trying to influence other political battles. Charles dipped a toe into last year's immigration reform debate when his institute co-sponsored a forum on the subject with BuzzFeed. His organization has lately waded into criminal justice reform, highlighting troubling racial disparities in the system and convening an event that featured a chapter president of the NAACP — an organization that in the past has condemned the political activities of the Koch brothers.

That's a start, but there are other ways the Kochs could nudge the Republican Party to a more moderate place. The brothers have traditionally avoided bankrolling advocacy on controversial social issues, but they would certainly throw a curveball to their opponents on the left (not to mention their supporters on the right) by actively backing the causes of marriage equality or reproductive rights. They could take a page from hedge-fund manager Paul Singer, a member of their donor network, who has emerged as a top backer of same-sex marriage.

The Kochs may fear jeopardizing their newfound power by actively supporting issues that could rile the GOP base. By challenging the Republican Party on some of its most entrenched positions, they would surely risk alienating allies, yet they stand to more than make up for that with new supporters whom the GOP has traditionally turned off or written off. But it all depends on whether Charles and David Koch are willing to take on the Republican Party once again, this time as insiders.

Twitter: @DanielSchulman

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