BY SHAILAGH MURRAYThe Washington Post WASHINGTON - A joke made its way around the Capitol Thursday: How do you know the 2008 election is really over? Because John McCain is causing trouble for Republicans again. Two and a half months removed from his defeat in the race for the presidency, colleagues say, McCain bears more resemblance to the unpredictable and frequently bipartisan colleague they have served with for decades then the man who ran an often scathing campaign against Barack Obama. In some instances, he's even carrying water for his former rival. . . . . . Sen. Lindsey Graham,...