This article is from the archive of our partner National Journal

Democrats have been worried about the African-American vote in Louisiana for months. But what really doomed Sen. Mary Landrieu's reelection bid was the near-monolithic white vote against her.

Landrieu's loss Saturday to Republican Sen.-elect Bill Cassidy followed a November all-party primary in which the incumbent got a lower share of the white vote (18 percent) than all other Democratic Senate candidates in the country but one, according to exit polling. There was no exit poll Saturday night due to a lack of media interest in the runoff, perhaps because even Landrieu's campaign acknowledged that she would need at least 30 percent support from white voters to win another term, a huge jump from her baseline in November.

That's about what Landrieu received when she won her final Senate term in 2008, and her drop-off since then highlights how the white voters who used to be the Democratic Party's Southern foundation have left—and how the party has collapsed without them.

"She came home to a sea of change since she last ran," said Bernie Pinsonat, a pollster in the state. "We don't have any Democratic statewide officials, after her, left. The Legislature is now dominated by Republicans; you don't even need a Democrat to pass a bill. Next year there will be maybe 10, or maybe eight or seven white Democrats left in the entire Capitol building. There's been a mass exodus and not something that had gone unnoticed. I don't know why she ran for reelection."

It's part of a regional trend. Though Landrieu was considered a strong candidate with a personal brand that might be able to cut through the partisan trends in Louisiana, her performance in 2014 mirrored B-list Democrats running in noncompetitive races throughout the South. The un-touted Democratic Senate candidates in South Carolina got the same share of the white vote as Landrieu, according to exit polls, while Mississippi Democrat Travis Childers pulled in 16 percent of whites in his blowout loss. Michelle Nunn in Georgia won Democrats' highest share of white voters in the South: 23 percent, not nearly enough to claim a victory over incoming GOP Sen. David Perdue.

Meanwhile, after Democratic Rep. John Barrow's loss in Georgia a month ago and Landrieu's on Saturday, there will not be a white Democrat from the Deep South (South Carolina, Georgia, Alabama, Mississippi, and Louisiana) in Congress in 2015. Democrats' representatives from that region are all African-Americans representing majority-minority districts, while the white voters who dominate the other districts have tilted them toward Republicans. In the South as a whole, even though Democrats picked up a congressional seat in the Florida Panhandle, Republicans will hold their highest-ever share of Southern House seats next year, too.

Back in Louisiana, Democrats' declining appeal among whites seemed to accelerate basically from the moment Landrieu won reelection in 2008.

"That 18 percent you noticed Landrieu got in November has been around for six years," Pinsonat said. "That has been the constant you looked at in surveys. Whether it's stimulus support or health care or immigration or Barack Obama himself or Mary Landrieu herself, it's all been pretty constant levels. Nobody could have been surprised on election night."

Landrieu's strategy during the campaign has been to try and separate her messaging to both encourage high African-American turnout and also persuade more white voters to vote for her one more time. The commercials her campaign and party have run on black radio play up her ties to Obama, with one recent ad calling for voters to stand with the president by supporting Landrieu. Meanwhile, her message to the general population has focused on the differences between herself and the president on issues including oil and gas—even as Cassidy and allied GOP groups have hammered her support for Obamacare and other administration priorities over the last six years.

"He's not for Keystone; I am. He shut down oil and gas drilling; we're all for it," Landrieu said of Obama in her final debate. But that wasn't enough to convince enough white voters to join Landrieu's African-American base in Louisiana, and it's why Landrieu won't be returning to the Senate next year, instead joining Democrats across the South in the losers' column.

This article is from the archive of our partner National Journal.

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