In the run-up to Texas’s closely watched Senate election, Republicans’ attempts to smear Beto O’Rourke centered on things like his college punk-rock band, his denunciation of the murder of a black man shot in his own apartment, and his arrest for hopping a fence at a university. Even their attempts to criticize him for a D.W.I.—a pitfall that, in a different age, could very well have torched his campaign—fell flat when O’Rourke pointed out he’d been transparent about the charge in past House races. In other words, about the only thing the G.O.P. succeeded in, per one headline, was making O’Rourke look “extremely cool.”

As he embarks on a solo tour outside of Texas to mull over whether to enter the Democratic field in 2020, however, skittish Republicans are working hard to ensure that his hypothetical road to the nomination would be decidedly bumpier. As The Hill reported on Tuesday, G.O.P. researchers have already begun to compile a “hefty” book of opposition research against O’Rourke—one that’s aimed squarely at his progressive bona fides. They’re reportedly focusing their research on O’Rourke’s cozy relationship with the oil and gas industry, which donated nearly half a million dollars to his campaign, as well as his state-level voting record: as a congressman from El Paso, O’Rourke voted for Trump administration policies about 30 percent of the time, and against his own party on several bills, including a measure that would have prevented oil drilling in the Gulf of Mexico, and another that gave special tax credits for COBRA insurance benefits. Also of note: O’Rourke’s family money, and his ties to fossil-fuel interests. “He’s very different from all the other progressives who are running for office, and I think he’s going to learn that the hard way,” one Democratic strategist who’s worked on presidential campaigns told The Hill. “It’s going to be so much worse than what he experienced in the midterms.”

The strategy, it seems, is to isolate O’Rourke from the far-left wing of the party by highlighting his capitulation to forces it detests. And, in fact, Bernie Sanders devotees are already primed to question O’Rourke’s progressive credentials. “They think the Establishment is always looking for someone to go against Sanders—to run against progressives in the party and stop them from being ascendant,” Georgetown University historian Michael Kazin recently told my colleague Peter Hamby. “I think they are suspicious of Beto because he has taken oil and gas money, he’s becoming the darling of big donors, and Obama likes him.” The hosts of Sanders-friendly podcast Chapo Trap House have railed against O’Rourke, accusing Democrats of “slapping a cool coat” on his centrism in a desperate attempt to field a candidate who they believe will attract a wider swath of voters.

If Republicans do manage to knock O’Rourke out of the primary, they will have done themselves a tremendous favor. Though he is still months away from reaching a verdict—reports suggest he’ll wait until at least February to decide whether to run for the Democratic nod—much of the G.O.P. sees O’Rourke as the most salient threat to the president. “A Democrat who can carry Ohio, Pennsylvania, Wisconsin, or North Carolina is problematic,” a Republican insider told my colleague David M. Drucker last month. “Someone like Beto, who can campaign on the fly, raise money, and excite young voters, could put those and other states in play.” Similarly, if Republicans are hoping to unseat O’Rourke by goading the left into opening fire, they’ll first have to contend with his disarming frankness, which could go a long way toward explaining those oil and gas connections—ties he maintained as a Texas lawmaker, where oil and gas make up a significant percentage of industry in the state. “His legislative record is relatively short,” David Wade, a former adviser to John Kerry, told The Hill. “His problematic votes are mostly home-state votes that could be managed if his larger narrative proves durable.”

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