From time to time until November 2012, I’ll be offering a snapshot of the emerging presidential race. This is the first. Here’s the headline: Given current national trends and a credible Republican nominee, the presidential election would be very, very close, and President Obama might even lose. The economic situation looks like it will not be good enough for the president to cruise to victory, yet it will not so bad that voters are in the mood to repudiate him. In such a situation, campaign tactics, branding, and the identity of the Republican nominee would likely determine the outcome of...