It’s a national — and international — trend. The polls underestimated the scope of the 2014 midterm elections. Elections and referenda in Greece, Poland, Britain, Israel, and Scotland embarrassed the pollsters who thought they knew what was going on.My colleague at the American Enterprise Institute, Karlyn Bowman, has been studying polling for decades. She says this may be “the end of polling as we know it.” Already, the venerable pollster Gallup has gotten out of the business of polling the presidential primaries and may not track the general election either. Pew, another polling titan, is fairly gun-shy about covering the presidential horse race as well.