By Alan Abramowitz

The distribution of party identification in the electorate is one of the most important factors influencing the outcomes of elections during any political era. From the 1930s through the 1980s, the Democratic Party enjoyed a substantial advantage over the Republican Party in voter loyalties. Since the 1980s, however, the Republican Party has made substantial gains in voter loyalty in the U.S. At present, the American electorate is almost evenly divided in its partisan loyalties: in the 2004 American National Election Study (ANES), 32 percent of American adults identified with the Democratic Party while 29 percent identified with the Republican Party. The 3 point Democratic advantage in party identification was the smallest in the 52 year history of the ANES.

The erosion of the traditional Democratic advantage in party identification over the past quarter century has contributed to Republican gains in national, state, and local elections. Despite the dramatic Republican gains in party identification, however, Democratic candidates have won a plurality of the popular vote in 3 of the past 4 presidential elections. Even in 2004, a Republican incumbent governing in a time of war won a surprisingly narrow victory over a Democratic challenger widely viewed as too liberal and too elitist by a large proportion of the electorate.

In order to explain the strong performance of Democratic presidential candidates in recent elections, one has to consider two other aspects of the recent realignment of voter loyalties in the United States: the increased loyalty of Democratic identifiers and the transformation of the independent voter.

Republican gains in party identification have been achieved largely among former conservative Democrats in the southern and border states. But these conservative Democrats were the least loyal Democratic voters, especially in presidential elections. As a result of their departure, the Democratic Party is now much more unified than in the past. Between 1952 and 1988, Democratic presidential candidates received an average of only 78 percent of the major party vote among Democratic identifiers. In contrast, during the same era Republican presidential candidates received an average of 91 percent of the major party vote among Republican identifiers. In the four presidential elections since 1988, however, Democratic presidential candidates have received an average of 93 percent of the major party vote among Democratic identifiers—even better than the average 91 percent support of Republican presidential candidates by Republican identifiers in these four elections.

The increased loyalty of Democratic identifiers is only part of the explanation for the strong performance of Democratic candidates in recent presidential elections, however. Just as important has been a dramatic change in the behavior of independent voters. Independent voters now comprise the largest segment of the American electorate. According to the ANES, independents made up 38 percent of entire electorate in 2004 and 33 percent of the actual voters. And these independent voters preferred John Kerry to George Bush by a decisive 58 to 42 percent margin. In the 2004 national exit poll, independents also favored Kerry over Bush, although by a smaller 51 to 49 percent margin.

Whether one accepts the ANES estimate of 58 percent or the exit poll estimate of 51 percent, the level of independent support for John Kerry in 2004 represented a dramatic turnaround from the traditional voting tendencies of independent identifiers. According to ANES data, in the 10 presidential elections between 1952 and 1988, Democratic candidates received an average of just 40 percent of the major party vote among independent identifiers. In the four presidential elections since 1988, however, Democratic candidates have received an average of 55 percent of the major party vote among independent identifiers.

The recent trend in presidential voting among independents is consistent with another trend in this group. Political scientists have long recognized that most independent identifiers are not totally neutral toward the two major parties. The large majority of independents lean toward one party or the other, and these leaning independents vote overwhelmingly for the party that they lean toward. In 2004, for example, according to the ANES, 88 percent of independent Democrats voted for John Kerry while 85 percent of independent Republicans voted for George Bush.

In 2004, 45 percent of independents expressed a preference for the Democratic Party while only 30 percent expressed a preference for the Republican Party. This 15 point Democratic advantage among independent identifiers was the second largest in the history of the ANES, topped only by a 16 point Democratic advantage in 1964, the year of the largest Democratic presidential landslide of the modern era. As recently as 1984 and 1988, leaning Republicans outnumbered leaning Democrats.

Why do a plurality of independent voters lean toward the Democratic Party? The answer appears to be that the social and political beliefs of independent identifiers are much closer to those of Democratic identifiers than to those of Republican identifiers. On the issue of abortion, for example, 58 percent of independents and 59 percent of Democrats in the 2004 ANES came down on the pro-choice side compared with 44 percent of Republicans. Similarly 41 percent of independents and 42 percent of Democrats supported gay marriage (no civil union option was offered in the NES survey) compared with only 17 percent of Republicans. On health insurance, 60 percent of Democrats and 53 percent of independents favored a larger government role compared with only 26 percent of Republicans, and on foreign policy, only 24 percent of Democrats and 33 percent of independents favored greater reliance on military force compared with 61 percent of Republicans.

Independents’ views of President Bush’s performance were also much more similar to those of Democrats than to those of Republicans. Only 11 percent of Democrats and 33 percent of independents approved of President Bush’s handling of the economy compared with 82 percent of Republicans and only 12 percent of Democrats and 37 percent of independents approved of Bush’s handling of the war in Iraq compared with 85 percent of Republicans.

The growing influence of the religious right is another factor that appears to be alienating many independent voters from the Republican Party. In fact, independent voters are less religious than either Democrats or Republicans: 56 percent of independent identifiers in the 2004 ANES indicated that they seldom or never attend religious services compared with 50 percent of Democratic identifiers and 42 percent of Republican identifiers.

These results suggest that the strong showing of Democratic candidates among independent voters in recent presidential elections reflected beliefs that are not likely to change in the short run. If anything, the policies pursued by the Bush Administration and its allies in the House and Senate since the 2004 election could further alienate independent voters. However, Democratic candidates need to do a better job of appealing to these independent voters in House and Senate as well as presidential elections. Focusing on issues on which Democrats and independents agree with each other and disagree with Republicans could help Democrats to make solid gains in the 2006 midterm elections.