Turning first to Bainbridge et al., we see the “anecdotes = data” argument. Bainbridge writes:

In the United States, the Electoral College makes it almost impossible for a third party candidiate to win the Presidency. Countries in which that is not true are not demonstrably better off. Look at the last Presidential election in France: In the first round of voting, Chirac led—but got less than 20% of the vote. Worse yet, nationalist nut-job and perrenial fringe party candidate Jean-Marie Le Pen qualified for the run-off with a mere 17%. Do Juan and Glenn think this is a model we should emulate?

Of course, the existence of two-round voting in and of itself didn’t create that outcome. France’s problem is a highly fractured party system, in which political parties (particularly on the right) come and go as personalistic movements rather than as ideological parties in any traditional sense of the term. Le Pen got to the second round largely because of bickering on the left between supporters of then-prime minister Lionel Jospin and other socialists, as well as due to protest voting from voters fed up with the failure of the mainstream parties to deal with France’s serious (and continuing) immigration crisis. None of this is present in the U.S., which means that the example of France is quite specious. Perhaps a better analogy would be the case of Louisiana, bearing in mind that a race like Edwards-Duke could have happened in any other state where primaries are used to select nominees.

Bainbridge goes on to write:

Anyway, I doubt very much whether most Americans are dying for third party candidates to have ballot access. As Bruce Bartlett observed: “The recent California election is evidence that there is no real demand for third parties. Despite the fact that anyone with $3500 could be on the ballot for governor and with 135 people running, 95.5 percent of the final vote went to candidates openly identifying themselves as either Republicans or Democrats.”

If I give two parties over a century to establish a brand name, then suddenly allow a third party to compete as well, chances are pretty good that the third party isn’t going to get a lot of support. Persistent third parties are something of a novel phenomenon in most of the U.S., and partisanship is largely inherited. If 4.5% of the final vote is going to parties other than the Republicans and Democrats, even with a variety of both Democrats and Republicans on the ballot to choose from (something you don’t normally see in any state other than Louisiana), I’d say that’s a pretty good showing, particularly due to the “psychological effect” of Duverger’s Law.

I think there’s also a broader way to look at third party runs than Taylor, Bainbridge, and Joyner acknowledge. It is true that, in the pure “rational choice” world envisioned by Anthony Downs and William Riker, voting for minor-party candidates is an irrational act—if you accept the premise that voting is solely a selection process, in which citizens only participate to choose political representatives. But I think (as I argue in the last substantive chapter of my dissertation) that the proper way to conceive of voting has two components: selection and expression. The extent to which (knowledgeable) voters engage in selection versus expression is largely driven by perceptions of how close the election (among major-party candidates) is and whether or not they conceive the differences between major-party candidates to be meaningful. If her vote is unlikely to change the outcome of the election, a voter is likely to choose to cast an expressive ballot—to display her preferences about public policy, for example. And this would not be an irrational act: look at Ross Perot’s 1992 candidacy, for example. Virtually nobody in Washington cared about balancing the budget in 1992, until millions of voters cast ballots for Perot. Suddenly, the Democrats and Republicans started running around trying to balance the budget. Nader’s 2000 candidacy arguably had a similar effect on this year’s Democratic race, where many of the themes Nader raised four years ago have resonated with primary voters and worked their way into the campaigns of all of the candidates.

There is also another way to look at Nader’s 2000 candidacy as being beneficial. His campaign energized a lot of young people about politics—and I suspect a lot of those young people went on to help more “mainstream” candidates in this year’s races, most notably Howard Dean’s campaign. Even if, like me, you don’t agree with their politics, I think that’s a generally positive outcome that makes our democracy healthier. A 2004 Nader run, even if it has no other effect, should bring another generation of 18–21 year olds into the process.

Finally, a brief point on Juan Non-Volokh’s suggestion that Nader’s campaign will help improve ballot access for third parties and independent candidates. I think the effects will be more nuanced; in states with Republican legislatures, I’d expect an improvement, while I think Democrats will try—at least behind the scenes*—to make Nader’s qualification for the ballot harder. I will say, however, that the effects of ballot access laws are hardly as benign as Steven Taylor suggests: they cause minor parties like the Libertarians to spend a significant chunk of their budgets on maintaining ballot access (petition drives, lawsuits, and the like), expenses that major parties are able to avoid due to grandfather clauses and historical exemptions—and every dollar these parties spend on ballot access is a dollar they can’t spend to support candidates or get their message out, further placing them at an institutional disadvantage.

* I don’t think they’ll do it in public, because it would be rank hypocrisy for Democrats to accuse Republicans of “stealing elections” at the same time they try to keep Nader off the ballot.