US Census Bureau site. Searchable repository of census data from the United States, Puerto Rico and the Island Areas including population, housing, and economic information. Accessible in English and Spanish. NOTE: This site will no longer be updated as of June 2019.
Global analytics and polling firm. Gallup conducts public polls on a variety of topics of national and international interest. Poll results are published in the News and the Reports section of their website, organized by topic.
Census QuickFacts provides statistics for all states and counties, and for cities and towns with a population of 5,000 or more. Searchable for statistical information on demographics, education, income, and health.