The morning after Republicans lost an upstate New York House seat, Sen. Lindsey Graham (R-S.C.) warned that conservative activists will bring destruction to the Republican Party if they drive out moderate candidates across the country. “To those people who are pursuing purity, you’ll become a club not a party,” Graham told POLITICO in the Capitol Wednesday. “Those people who are trying to embrace conservatism in a thoughtful way that fits the region and the state and the district are going to do well. Conservativism is an asset. Blind ideology is not.” Graham, who has sparred with his party’s right wing...