It was a priceless photo for a Republican governor running for reelection in a blue state: Him standing at the mike, the two Democratic legislative leaders at his side. All three grinning into the cameras in the Capitol news conference room — announcing their bipartisan agreement last week on a bill to raise the minimum wage. But that was not an abnormal picture in this atypical year. Bipartisan deals, aberrant in the past, have become commonplace: a $37.3-billion package of state bonds for public works, a rare on-time budget and — the most recent — legislation forcing drug companies to...