The GOP primaries could be contested by 10 or more candidates and, at least a few of them are not daffy, right-wing cartoon characters. When it comes to the general election, whatever the poll numbers are now, the race will surely tighten. This is, after all, a nation that is sharply divided, politically, and Republicans can count on a base of about 45 percent of the electorate. That means a reasonably sane conservative like Jeb Bush, Rand Paul or Marco Rubio could be competitive under any circumstances. Even a bland, county-level political talent like Wisconsin Gov. Scott Walker could make it a race, given how much some people detest the idea of another Clinton as president.