"I love data." Mitt Romney has been speaking for less than two minutes when he makes this profession. The former Massachusetts governor is meeting with the editorial board of The Wall Street Journal to discuss his campaign for the presidency. And he starts not with the economy, "global jihad" or the country as a whole, but with himself. While some have questioned Mr. Romney's authenticity, the immediate impression he gives is that he speaks straight from the heart. Especially where data are concerned. "I used to call it 'wallowing in the data,' " Mr. Romney continues. "Let me see the...