In a message to supporters sent just before 11 p.m. Friday night, Representative Ron Paul, a long-shot G.O.P. candidate from Texas, basically conceded that he’s not going to win the party’s nomination. That said, he’s scaling back his campaign — but not entirely. He said: With Romney gone, the chances of a brokered convention are nearly zero. But that does not affect my determination to fight on, in every caucus and primary remaining, and at the convention for our ideas, with just as many delegates as I can get. But with so many primaries and caucuses now over, we do...