Only a month ago, pollsters saw unmistakable signs of a Democratic blue wave–some even called it a tsunami–in the fall’s midterm elections. That’s because, in a generic Congressional ballot, an unnamed Democrat was seen as likely to beat an unnamed Republican by more than 10 points. But now, the generic ballot preference for Democrats has fallen to just 6 points. Are Republicans benefiting from their tax-cut package? Did the government shutdown hurt Democrats? Are President Trump’s attacks on the FBI bringing home some of his erstwhile supporters? It’s hard to say and November is still a long way off. But this should be a wake-up to progressives that they have to fight for every last vote if they are to flip the House.