According to a 2013 Gallup poll, the most democratic states are New York, Massachusetts, Hawaii, Rhode Island and Maryland. The heaviest concentration of democratic states is on the East Coast.
As of 2013, there were more Democratic states than Republican states in the U.S., though there were fewer in 2013 than during the 2012 presidential election. Democratic states are usually referred to as "blue" states, while Republican states are "red."
The determination of whether a state is solidly red or blue is made by the percentage of a state's voting population that professes to be members of a particular party. Those states with 10 or more percentage points in favor of one party over the other are considered to be "Democratic" or "Republican."
States in which neither party is favored by more than 10 percentage points are considered swing states. Experts generally expect those states to lean in favor of one party over the other, but neither party has a significant enough advantage to guarantee carrying the state in elections. States can swing in favor of one party over the other as the result of party turnover in Congress following elections, the effect of a specific candidate or simply through a change in voter sentiment.