The clearest way to get a picture of how well Democrats are doing in 2018 is to go down the list of recent special state legislative elections: * A Florida state legislative district that Donald Trump won by five points, according to data from liberal political blog Daily Kos, is now in the hands of Democrats, who won it by eight points this month. * In January, Democrats flipped a Wisconsin state legislative district that Trump won by 20 points. * A few weeks later, Democrats flipped a Missouri state legislative district that Trump won by nearly 30 points, for...