Finally, the candidate who ultimately wins the nomination is likely to be the one who shows the greatest ability to unite the party and draw others into the GOP fold. This was one of Ronald Reagan’s great strengths. No candidate in the GOP field possesses Reagan’s political gifts. But they should seek to emulate his appeal to both committed Republicans and to disaffected Democrats and independents in a principled and optimistic manner…

But done right, a long and competitive primary season could be very healthy for the GOP, drawing the country’s interest, boosting Republican registrations, recruiting volunteers, and sharpening its message.

Mr. Obama is extremely weak right now. It’s an open question whether he possesses the political skills that allowed other presidents (like Bill Clinton) to recover. The results of his policies may prevent his recovery, not enable it, as with Reagan. Republicans should not count on Mr. Obama imploding but assume the race ahead will be difficult. If history is any guide, it will be.