Dan’s post reminds me of something I wrote when Ron Paul decided against a third-party bid. If he had run and John McCain won, Paul would have been blamed for splitting the antiwar vote. If a Democrat won, Paul would have been blamed for splitting the conservative vote. Perhaps Bob Barr will have a similar dilemma, though right now he seems likely to do the most damage to Barack Obama’s former Senate opponent Alan Keyes.
Let’s not forget a group potentially much larger than the Obamacons: the Obamacans. The typical Republican supporter of Obama won’t be a paleo-ish antiwar conservative but a disgruntled moderate. Nothing in Barr’s record or personae suggests that he’d have much appeal to these voters, except a few fiscal conservative/social liberal types who might like voting for a Libertarian famous enough to get media coverage. For most of these moderates, however, Barr will remind them of the kind of Republican who made them feel alienated from their party in the first place — Southern, socially conservative, and pro-impeachment. If Obama doesn’t get many crossover votes from moderate Republicans, it will be because McCain’s maverick image helps him appeal to centrist voters even when they disagree with him on major issues.
Obviously, I’m assuming that Obama will be the Democratic nominee, Barr the Libertarian, and Keyes the Constitution Party candidate, none of which is guaranteed.