It wasn't long ago that the conservative, free-market Club for Growth was viewed by a swath of Republicans as a furtive, well-heeled enemy whose efforts to purge moderates from the GOP had to be thwarted. The club and its agenda are "not representative of the Republican Party," the director of the Republican Main Street Partnership, a group of moderate GOP congressional members, once said, adding: "We raise money on a daily basis to defeat them." When asked this week about the Republican animus the group faced in the recent past, Club for Growth executive director David Keating replied: "That sounds...