Happy Birthday to Paul Krugman, 59, blogger, columnist, and, oh yeah, a pretty good economist, from what I understand.
1. Fascinating reporting on Rick Santorum's college days, by Molly Redden.
2. Dana Goldstein on Santorum, Barack Obama, and vocational education.
3. Where did Santorum get his take on JFK? Sarah Posner explains. See also a good Ed Kilgore post.
4. David Frum really, really didn't like Mitt Romney's Detroit speech -- the substance, that is.
5. And an outstanding AP story, by Malcolm Ritter, about voters in primary elections.