Lexington: The politics of purity A FIGHT has broken out within the Republican Party. On the face of it, rival camps - broadly, the establishment versus the insurgent right - are arguing about why they lost the last election, and how to stop losing. The loudest name-calling involves a new political fund backed by Karl Rove, election guru to the Bush dynasty and a man with access to deep-pocketed donors. It is one of several establishment wheezes aimed at asserting more control over party primaries that pick candidates for big races. For his pains, Mr Rove has been called a bully and a fake conservative by the right of his party, which once he happily exploited. At the same time, for the bigwigs, Haley Barbour, a former governor of Mississippi and past chairman of the Republican National Committee, has urged donors to stop giving to the Club for Growth, an anti-tax group that weighs in on primaries from the right, savaging Republicans it deems insufficiently flinty. There is breathless talk of civil war as each side blames the other for losing races that were in the party's grasp. Actually, it is worse than that. The warring factions (mostly) agree that losing is bad. Their big dispute is over the Republicans who win elections. Start with the losers. Grandees blame a rainbow array of zealots - whether from the tea party or from anti-government or socially conservative groups - for picking unelectable candidates in half a dozen winnable Senate races in 2010 and 2012. A prize exhibit is Todd Akin, whose Senate bid in Missouri imploded after he claimed that women subjected to rape rarely become pregnant, because their bodies "shut that whole thing down." Grandees wistfully cite the 1967 advice of William F. Buckley, a swashbuckling conservative, that wise primary voters back the most right-wing "viable" candidate. Outside groups such as the Club for Growth and FreedomWorks, as well as tea-party outfits, have rebuttals ready. They note that establishment-backed Senate candidates, from North Dakota to Montana or Virginia, also lost winnable races in 2012. And they can point to rising stars elected with their help, upsetting party heavyweights in the process: above all Senator Marco Rubio of Florida, elected in 2010 and hailed by colleagues for his ability to talk about limited government without seeming a heartless scold, and to do it in Spanish, too. As for Mr Akin, it is argued, it was religious conservatives who powered his primary win, not tea partiers (a diverse bunch united in an angry distrust of government). The Akin case is not interesting, says Chris Chocola, the Club for Growth's boss: he lost because he made "really stupid comments." If insurgents wanted to be (even more) awkward, they could note that Mr Rove and his like once embraced the same religious forces that empowered Mr Akin, using gay-marriage ballots and other gimmicks to drive up Republican turnout at the 2004 election, blurring divisions between social and economic conservatives in ways that still harm the party among centrist voters. Yet beyond the finger-pointing, establishment Republicans and insurgents broadly share the goal of avoiding Akin-style losers. Their really poisonous disagreement involves Akin-style winners. Before he was undone by the scrutiny that comes with a statewide Senate race, Mr Akin was a six-term member of the House of Representatives, maintaining a posture of insurgency via hardline votes and clashes with party leaders. He won his last House election with 68% of the vote. It is the collective power wielded by Republicans from such safe districts and their distaste for compromise (strongly reinforced by fears of primary challenges if their purity wavers), that really divides establishment Republicans from the insurgent right. Steven Law, head of the new Rove-backed fighting fund, the Conservative Victory Project, has vowed to "institutionalise the Buckley rule" by vetting primary candidates, notably in Senate races. He stands ready to blast unelectable primary contenders with TV attack ads, if need be. Mr Law named Steve King - an anti-immigration hardliner from the House of Representatives who is pondering a Senate run in Iowa - as someone with a "Todd Akin problem." Mr King's antics include building a model border fence in the House chamber (electrified, he noted: as we do "with livestock"), and calling immigration a "slow-motion terrorist attack." After being denounced, Mr King e-mailed supporters for donations to fight "Karl Rove and his hefty war-chest." Another fighting fund, run by the centrist Republican Main Street Partnership, will intervene in primaries to defend moderates - or what its boss Steve LaTourette, a former congressman from Ohio, calls the "governing wing of the Republican Party." Who are you calling electable? Insurgents of the right indignantly reject "electability" as a test in primaries, thinking it a cover for Republicans willing to trim and compromise. They prefer "principled" as a label, insisting that when Republicans argue for smaller government clearly and bravely, they can win general elections "anywhere." As for Republican primary voters, beams Mr Chocola, they will choose principle over the party establishment every time. He may be right if the establishment's main weapon is television advertising, funded from afar. Money in politics is like the wind in sailing, says Mark Weaver, an Ohio campaign consultant. Nothing moves without it, but someone still has to steer: primaries are won when money and the grassroots combine. The Republicans have a problem with primaries. Most visibly, the contests have saddled the party with high-profile losers. But they also promote extremism among those who go on to win many races, harming the Republican national brand. Fixing that may enrage the party's different insurgent tribes. But grandees know the Republicans" future depends on it.