Jim Geraghty points out that Alan Keyes was invited to the last Republican debate but was ill-treated, while similar-polling candidates on the Democratic side (e.g. Dennis Kucinich, Mike Gravel) were not invited to the Democratic debate. He doesn't mention that Duncan Hunter and Tom Tancredo were also invited despite not performing well in polls, but that further confirms his point.
His explanation is that they wanted to make Republicans look bad by including the more radical elements but without doing so with the Democrats. While I'm certainly open to such an interpretation (bad motives abound in this world), I'm curious if there are more charitable explanations of why they would have treated the two parties differently on this issue. I can't think of any, but I'm curious to hear any plausible suggestions, because I do think it's a bit strange.
The criteria to be included were: 1) an FEC statement of candidacy; 2) having an Iowa campaign staffer and Iowa campaign office as of October 1; and 3) registering at least at 1% in the October Des Moines Register poll. This should have been known to Kucinich and Gravel. Kucinich has a staffer who works out of his home, but has not met the criteria of a full-time paid staffer or rented office space. Keyes did meet all the requirements, and so was considered a serious candidate in Iowa. While I agree that the situation was better for Democrats than Republicans, that doesn't mean there was a conspiracy.
OK, that does sound consistent. I suppose Geraghty might argue that they found some arbitrary criteria designed to exclude certain people and allow certain people, but I think he'd need to make the case for that rather than just assume it.