It's not just the economic numbers that are looking up for President Obama. A new New York Times/CBS News poll puts his approval rating at 50 percent, his highest mark since May 2010 (except for a brief bump after Navy Seals killed Osama bin Laden in May). That's a couple of points better than the RealClearPolitics average as displayed in the chart, but the uptrend is clear. Now, let’s assume the economy continues to grow—not gangbusters, but something along the lines predicted by economists in the recent Wall Street Journal survey. We’re talking slow-but-steady 2.5 percent GDP growth and a...