Companies conduct or hire an agency to conduct opinion polls in the U.S., particularly as a general election approaches. Since it is possible to produce fake polling numbers,[1] third parties have attempted to identify which are reliable or unreliable sources of polling information. These include FiveThirtyEight, who uses a rating system that claims to correct biases of polling agencies,[2] and more neutral analyses and polling averages, such as RealClearPolitics.
Polling agencies take various approaches, or methodologies, in their attempts to calculate accurate levels of support for each party or candidate. The Trafalgar Group includes in its calculations "silent Trump voters," who they claim support Trump but do not tell pollsters their voting preference,[3] and left-wing pollsters, such as Data for Progress.[4]
Polling agencies tend to produce figures most in line with their own political perspective, such as "voters want to cancel fossil fuels", according to Data for Progress,[5] or "Most Agree With Trump On Need for 'Patriotic Education'", according to Rasmussen Reports.[6]