Yuval: I suspect that the real reason that people who are favorably disposed to Romney, Christie, or Jeb Bush as the Republican nominee want only one of them to run is not that they are worried about the primary contest dragging on too long. Their real worry is probably that with a split in this portion of the primary electorate, someone they like a lot less, and consider less electable, will win the primaries. And my guess is that at the top of the list of candidates they do not want to see win the nomination are Ted Cruz (an old friend of mine) and Rand Paul.