The end of a marathon presidential campaign cleared space in the news cycle this week for buffeted politicians to try to rehab images scarred by scandal or brutal campaigning. John McCain made an appearance on “The Tonight Show” on Tuesday and made light of his failed campaign. “The one thing I think Americans don’t want is a sore loser,” McCain told host Jay Leno. “I knew I had a headwind. I can read the polls. They tried to keep them away from me. But I knew we had a real headwind.” The Rep