Probably like most of you, I'm interested in political science not just to learn how the world works, but to change it. That's why I co-founded BoldProgressives.org, a group to help get progressive candidates elected. Our current campaign is about pushing Norm Coleman to end his pointless legal challenges by getting people to donate a dollar for each day he stays in the race -- see right.

But Matt Yglesias notes that mainstream political science seems to think not much can be done to affect whether Republicans or Democrats win. "That kind of nihilistic point of view", he complains is "disappointing to political activists who like to think that sharper arguments or exciting new facts are likely to swing things."

Is there hope?

Perhaps some political activists are hardcore Rahm Emanuel-style partisans who don't care about anything except whether the guy who wins has a D next to his name instead of an R, but I think most political activists are (like me) in it because their want their policy to win, not their party.

If the pure nihilistic view is right, and we can't really affect whether a Democrat or Republican wins an election, then there's one obvious way to help our policies succeed: make sure people who support them win the primary. That's the strategy we follow at BoldProgressives.org -- we don't just support the Democrats, we push them to be bolder.

Gelman says he found "most individual members of the House and Senate have quite a lot of flexibility in the policies they could hold, and still have a very good chance of reelection", which means progressives could stand to be quite a bit bolder. Specifically, Gelman estimates that the most extreme candidates will only lose 3% of the vote compared to the most moderate. By contrast, just being an incumbent tends to win you 10%.

I think this is a lesson the right has learned well. For decades now, they've been electing conviction politicians who take firm stands and try to lead the public on policy positions instead of simply following the shifting winds of the polls and trying to maximize their appeal. On the left, the last major person to take this view was Paul Wellstone, whose controversial stands like opposition to the invasion of Iraq were greeted with support: "I don't always agree with you," voters would tell him, "but at least I know where you stand."

Instead of looking at how politicians can and do follow public opinion, perhaps we should spend some time on how public opinion can follow politicians. Another one of the findings of political science is that voters put a lot of faith in what members of their party say. If that's the case, it seems like activists have a lot to gain by getting members of their party to be bolder.