Determining whether or not a speaker supports a proposal falls within the realm of sentiment analysis, an extremely active research area devoted to the computational treatment of subjective or opinion-oriented language (early work includes Wiebe and Rapaport (1988), Hearst (1992), Sack (1994), and Wiebe (1994); see Esuli (2006) for an active bibliography).
we extracted from GovTrack all available transcripts of U.S. floor debates in the House of Representatives for the year 2005 (3268 pages of transcripts in total), together with voting records for all roll-call votes during that year.