While most political maps show the United States as a collection of blue, red and undecided states, some sites such as YouGov.com have maps that highlight states that lean toward a certain party, including the red states. Other sites, such as 270towin.com, have a breakdown of every state's voting history.
YouGov's map of the red states uses U.S. presidential elections between 1992 and 2008 and highlights 25 states that have been favorable to Republican candidates. However, the red states shown on a map can vary by which elections the mapmaker chooses to examine. 270towin.com's map uses elections between 2000 and 2012 and highlights 20 states where Republicans are favored over Democrats.