Today, nearly all of the Democrats holding federal or statewide office in the South will represent so-called “majority-minority” districts or areas with a large number of new residents from outside the region. In the states of the former Confederacy, Democrats will control Senate seats or governors’ mansions only in Virginia and Florida. Not coincidentally, those are the two Southern states where people born outside the state represent a majority of the population. These Democrats bear little resemblance to the Southern Democrats who won by attracting conservative white voters.
The dramatic decline of the Southern Democrats represents the culmination of a half-century of political realignment along racial and cultural lines. “Some of it is about Obama; most of it is about the longer-term realignment of white voter preferences,” said Guy Molyneux, a Democratic strategist. The shift has contributed to the polarization of national politics by replacing conservative Democrats, who often voted across party lines, with conservative Republicans who do not.
But white support for Republicans in the South might rival, or in some places even exceed, white support for Democrats during the Solid South. In the November election, Ms. Landrieu received only 18 percent of the white vote, according to the exit polls, a figure nearly identical to the 19 percent of the vote that Republicans averaged in the state’s presidential elections from 1880 through 1948. The exit polls showed that Mr. Obama won 14 percent of white voters in Louisiana in 2008.
“It’s a completely different party than it was 20 or 30 years ago,” said Merle Black, a professor of political science at Emory University. “When the Democratic Party and its candidates become more liberal on culture and religion, that’s not a party that’s advocating what these whites value or think.”
The demise of the Southern Democrats now puts the party at a distinct structural disadvantage in Congress, particularly in the House. The young, nonwhite and urban voters who have allowed Democrats to win in presidential elections are inefficiently concentrated in dense urban areas, where they are naturally drawn into overwhelmingly Democratic districts by congressional mapmakers. They are also concentrated in populous states, like California and New York, which get the same number of senators as Alabama or Mississippi.