Yesterday five Democratic candidates (Obama, Edwards, Richardson, Biden, Kucinich) pulled their name off the ballot for the January 15 presidential primary in Michigan, leaving Christopher Dodd as the only obstacle to a victory by Hillary Clinton in that state. (And both Clinton and Dodd have promised not to actually campaign in Michigan.) See Boston Globe story here.

The reason for boycotting a state of 10 million people is to avoid offending New Hampshire’s 1.3 million people and their first-in-the-nation primary. But I’m not writing to criticize New Hampshire Democratic primary voters, who have done an admirable job of objectively scrutinizing all the presidential candidates and then usually picking someone from Massachusetts (Dukakis, Tsongas, Kerry).

I’m more disappointed by the lack of juicy data that could have come out of a contested Michigan primary. Michigan would have been Hillary Clinton’s first real primary contest in a major state (she never had any credible Democratic challengers running for the US Senate in New York), and it would have provided a lot of clues about her potential strength in wealthy suburbs, blue-collar cities, and rural areas outside of idiosyncratic New England. It also would have been revealing to compare turnout on the Democratic and Republican sides of the primary, to see which party is better at getting out their voters.

Of course, we’ll get this kind of data from the February 5 mega-primary of more than 20 states — if the contest lasts that long, which will happen only if Clinton loses in Iowa, New Hampshire, or South Carolina. Ironically, the patron saint of long-shot candidates, Jimmy Carter, won the Democratic nomination in 1976 largely because he was the only one who competed in every contest, whether it was a caucus, a primary, or a “beauty contest” that didn’t actually award convention delegates. (Michigan in 2008 may actually fall into that last category.) The constant news stories about Carter victories overwhelmed the candidates who had decided to compete in only a few selected states.