On the Ballot: Bipartisan couples face tough odds. But these pairs make it work

Democratic California Gov. Gavin Newsom and U.S. Ambassador to Greece Kimberly Guilfoyle. Democratic strategist James Carville and GOP consultant Mary Matalin. Former GOP California Gov. Arnold Schwarzenegger and Kennedy scion Maria Shriver. These are just a few famous examples of some of the most prominent and well-known — past and present — bipartisan relationships in American politics — a phenomenon that some researchers believe make up as much as a quarter of U.S. romantic relationships. Dating...