First, I have charted the percentages for each ideology and moderates for the presidential elections from 2000 to 2012:I have also charted each ideology in terms of voter turnout, support for Democrats, and support for Republicans during each presidential election year since 2000. The charts are below:
What are we to make of these? As one would anticipate, the loyalty to Democrats is greatest among liberals, populists, and moderates. Conversely, loyalty to Republicans is greatest among conservatives and libertarians. Only in 2004 were moderates more loyal to Republicans than to Democrats.
Concerning the size of each ideology in the electorate, the percentage of conservatives and liberals are nearly the same. Libertarians and populists are usually smaller, but the percentage of libertarians has grown in the last two elections. The percentage of moderates has also grown slightly since 2000. What’s your interpretation of the data?