Survey research is a central element of election campaigns. This chapter analyzes how campaigns use survey research. Campaign operatives use polling to help make key decisions throughout the race. They use polling to hone the message, broadly define the targeting, and make adjustments to resource allocation. The challenges facing polling are numerous, and it is important for pollsters to be accurate in order to keep the trust of candidates and political operatives who hire them. Political polling faces many challenges, but it is adapting to the changing times. A brief history of political polling underscores that the industry is scarred by a pair of seminal events early in its history. From 1996 to 2004, House and Senate races were primarily determined by the four elements of a winning campaign, because the political environment was not as dominant a factor.