George Washington was concerned about sectionalism potentially tearing the United States apart. His fears were somewhat justified as a sharp divide emerged very early on between north and south. When the question of slavery entered the national political debate, the bitterness of sectional partisan politics eventually led the country into Civil War. After the Civil War, other sectional divisions became evident as well -- between east and west, between the urban coasts and the rural interior. Just look at recent electoral maps, and you'll see how very alive sectional politics still is.
Early in its history, American electoral politics evolved into a two party system, with occasional third parties playing a spoiler or power broker role. While in the European parliamentary system, multi-party systems with "coalition governments" evolved, in America it's been a two-party, winner-takes-all game.
In Europe, each interest group has its own party. You have labor parties, religious parties, green parties, nationalist parties, and so on. These smaller parties then form coalitions with each other in order to form the majorities that can govern their nations. In the American Party system, the coalitions are internal to the two major parties. The Republican Party today, if we were in a European-style parliamentary system, would likely be a coaltion of the Religious Right Party, the Big Business Party, and the White Supremacy/Nativist Party. The Democratic Party would be a coalition of the African American Party, the Gay Rights Party, the Women's Rights Party, the Immigrants' Rights Party, the Working Man's Party, and so on.
The coalitions and alliances that have formed the basis of the American two-party system have shifted dramatically over time. For instance, after the end of the Civil War, thanks to the Republican Party's role in ending slavery and giving the vote to African Americans, the Republican Party became the party of African Americans, while the Democratic Party became the bastion of white Southerners. Under John F. Kennedy and Lyndon B. Johnson in the 1960s, the national Democratic Party supported voting rights and anti-discrimination legislation. In the process, the Democratic Party lost the support of white southerners, and won the loyalty of black voters across the country. Watch the electoral maps after the 1960s, and see how the southern states, once solidly blue, turn solidly red.
But while certain elements or factions have shifted considerably, one constant has been that the Democratic Party has always viewed itself as the "peoples' party," while their opponents -- first Federalists, then Independent Republicans or National Republicans, then Whigs, and last the Republican Party -- have been the party of wealth and corporate interests. This is not to say that the corporate interests have not managed to get their fingers into the workings of the Democratic Party as well. Toward the end of the 19th century, when both parties were hostage to big money, it took a major grass roots rebellion of populists and progressives to force the parties to pay attention to the needs of ordinary individuals. Certainly, the Republican Party has had its populist elements as well. It had to, or it could not have survived. But the Republican Party's strategy has always been to use social issues -- religion, race, ethnicity, "family values" -- to keep middle class and working class Americans divided, while it has pushed an agenda that favors big money. To the extent that the Democratic Party stopped functioning effectively as the party of the working man, they have lost the loyalty of ordinary Americans. If there is one lesson to be learned from the history of "red states" and "blue states" it is that the Democratic Party can only win when it lives up to its claim to be te "Peoples' Party."