There’s a scenario, believe it or not, in which Scott Brown’s stunning win last night could actually end up forestalling a massive G.O.P. sweep next November. It involves Barack Obama swallowing his pride, behaving like a President who’s just been thumped, and making a very public show of internalizing the lessons of last night in Massachusetts. And it involves dismissing, immediately and with prejudice, the liberal fantasy that Rahm Emanuel should spend the next few weeks “knocking heads together” in the House, in the hopes of pushing the Senate bill through Congress.