When Paul D. Ryan and Joseph R. Biden squared off during a vice presidential debate at a small Kentucky college four years ago, perhaps the last place they expected to meet again would be seated above the House floor for President Barack Obama's final State of the Union address. But in the moments before the president began a speech about ending partisanship, the Republican speaker and the Democratic vice president chatted amiably for several minutes.
Around them the House chamber buzzed with a hundred conversations. Agriculture Secretary Tom Vilsack gravitated to the bright red sweater-vest of Sen. Charles E. Grassley, R-Iowa, with Sen. Joni Ernst, R-Iowa, joining them. Republican presidential hopeful Marco Rubio of Florida, back in Washington tending to senatorial duties, ended up chatting and laughing with Sens. John McCain, R-Ariz., and Lindsey Graham, R-S.C. Graham has returned to the Senate full time, of course, having pulled the plug on his own 2016 White House bid.