Ed Kilgore: “While there are plenty of race ratings and election forecasts weighing the odds of a Democratic takeover of the U.S. House of Representatives in November, the single most reliable indicator historically has been the so-called generic congressional ballot, a poll question asking voters which party they want to control the House.”“It has probably become a bit more reliable of late given the steady rise of straight-ticket voting. And right now, the generic ballot numbers are spiking for the Democratic Party.”Check the Polling Dashboard for the latest.