Debate-shy: Candidates aren't sharing the stage like they used to

Debates in political campaigns used to be a given. Today, candidates increasingly view them as optional — or a political liability to be avoided.Why it matters: In a midterm cycle dominated by unprecedented spending on contrast ads, the candidates themselves are remarkably reluctant to challenge each other face-to-face.It's a sign of how campaigns have evolved, and an erosion of norms: Candidates — fueled by their parties and super PACs — still try to tear apart the opposition, they just do it from a distance.In the age of short, shareable video clips, TV debates offer candidates equal parts o