US Senate is the venue of political debates where the federal bills are formed and voted. Senators show their support/opposition along the bills with their votes. This information makes it possible to extract the polarity of the senators. We use signed bipartite graphs for modeling debates, and we propose an algorithm for partitioning both the senators, and the bills comprising the debate into binary opposing camps. Simultaneously, our algorithm scales both the senators and the bills on a univariate scale. Using this scale, a researcher can identify moderate and partisan senators within each camp, and polarizing vs. unifying bills. We applied our algorithm on all the terms of the US Senate to the date for longitudinal analysis and developed a web based interactive user interface www.PartisanScale.com to visualize the analysis. Copyright is held by the International World Wide Web Conference Committee (IW3C2).