U.S. elections are increasingly biased against moderates.

• Author: Niskanen, William A.
• Position: 2002 congressional elections

One important pattern in the 2002 congressional elections may have important implications for the 2004 elections and the future of American politics: the most vulnerable incumbents were moderates who had sometimes voted with the other party on an important issue.

I first suspected this pattern on reading the next-day newspaper reports of the election results. Sens. Jean Carnahan (D-Mo.) and Max Cleland (D-Ga.) lost, Sen. Mary Landrieu (D-La.) faced a December runoff election, and Sen. Tim Johnson (D-S.Dak.) faced a potential recount; all four, for example, had voted for the Bush tax cut and had campaigned as moderates. The only Senate Republican to lose was Tim Hutchinson of Arkansas, a conservative who had been involved in a personal scandal; (there must be something in the water in Arkansas). The most visible House Republican to lose was Connie Morella of Maryland, who had made a career of being a moderate and had voted against the Iraq war resolution. Before making any statistical analysis, I reported this suspected pattern and the potential implications of this pattern in a November 20, 2002, op-ed in the Investor's Business Daily.

To my knowledge, the only other person to report this pattern was David Broder, a leading political commentator. In a January 2, 2003, column in the Washington Post, Broder observed that party

caucuses on both sides of the Capitol have become more cohesive internally and further apart from each other philosophically.... with almost every session, (there are) fewer moderates or progressives on the Republican side and fewer conservatives among the Democrats--especially when it comes to fundamental economic and social questions and the role of government in American life. This article first summarizes my statistical analysis of the 2002 congressional elections to test the hypothesis that the most vulnerable incumbents in this election were moderates. The implications of these findings for voting theory, the distribution of the ideological positions of the winning candidates, and the problems of governing are then considered.

A Statistical Analysis of the 2002 Congressional Elections

My null hypothesis, again, is that the most vulnerable incumbents in the 2002 congressional elections were moderates. My measure of the moderation of Republican incumbents is their Americans for Democratic Action rating during the first session of the 107th Congress. Similarly, my measure of the moderation of Democratic incumbents is...