The single most obvious factor in Mr. Brown's loss was his inability to turn out his base. He did reasonably well in his home county of Prince George's, by historical standards. He beat Mr. Hogan by 143,000 votes there, a better total than Gov. Martin O'Malley managed in his first run. But overall, he netted 120,000 fewer votes out of the so-called "Big Three" — Montgomery, Prince George's and Baltimore City — than Mr. O'Malley did four years ago in what was also a great year for Republicans nationally. Considering that Mr. Hogan's current margin of victory stands at under 77,000, that's a big deal. He didn't win because he turned out rural and conservative suburban voters in unprecedented numbers; he won because Mr. Brown didn't excite the Democratic base.