The section of the Atlas that includes primary returns for US President have been updated to include official results from Presidential Primaries in the 2004 Democratic contest (county maps, congressional district maps, and data). All caucus events and several primary events were run by the Democratic party and therefore these results are obtained from the respective state Democratic Party organizations (and not from official state election agencies). In some cases, these data are incomplete due to the inability to obtain final and complete data from the state parties. A complete spreadsheet of the data is available for purchase from the store page.