Politifact– PolitiFact rates the accuracy of claims by elected officials and others who speak up in American politics.
Fact Check– They monitor the factual accuracy of what is said by major U.S. political players in the form of TV ads, debates, speeches, interviews and news releases.
Open Secrets– tracking money in U.S. politics and its effect on elections and public policy. Open Secrets are by far the best source for discovering how much and where candidates get their money. They also track lobbying groups and whom they are funding.
Snopes– Snopes has been the definitive Internet reference source for urban legends, folklore, myths, rumors, and misinformation for a long time.
The Sunlight Foundation– uses the tools of civic tech, open data, policy analysis and journalism to make our government and politics more accountable and transparent to all. Sunlight primarily focuses on money’s role in politics.
Poynter Institute– The Poynter Institute is not a true fact checking service. They are however a leader in distinguished journalism and produce nothing but credible and evidence based content.
Flack Check– . The site provides resources designed to help viewers recognize flaws in arguments in general and political ads in particular.
Truth or Fiction– Very similar to Snopes. They tend to focus more on political rumors and hoaxes.
Hoax Slayer– Another service that debunks or validates internet rumors and hoaxes.
Fact Checker by the Washington Post– Their fact checks are excellent and sourced; however their bias is reflected in the fact that they fact check right wing claims more than left.