In the final insult of a devastating 2014 election for Democrats, Sen. Mary Landrieu, the party’s last remaining statewide officeholder from the Deep South, was trounced Saturday in the head-to-head Louisiana Senate runoff election.

Republican Bill Cassidy’s resounding victory is the ninth Senate seat picked up by the GOP in this year’s elections, three more than the party needed to take control of the chamber. With nearly all the ballots counted, Cassidy led Landrieu by 14 points, 57 percent to 43 percent.


“On November 4th, the American people sent a message that they didn’t like the direction our country was heading,” Cassidy said in his victory speech. “Our state is the exclamation mark on that message.”

His win gives Republicans a four-seat cushion going into 2016, when the party is seeking to protect its first Senate majority since 2006. The next election cycle’s Senate map is as bad for Republicans as this year’s was for Democrats, with the GOP forced to defend seven seats in states President Barack Obama carried twice.

( Also on POLITICO: Greens to Landrieu: Good riddance)

Landrieu, the three-term incumbent who chairs the Senate Energy Committee, found herself cut off and left for dead by national Democrats after party strategists decided she had no realistic path to victory in Saturday’s Bayou State runoff. She lost much of her clout when Democrats lost their majority, and her failure to pass legislation to move forward with the Keystone XL pipeline in the lame duck session last month made her look politically impotent.

Cassidy, a medical doctor, first elected to a Baton Rouge-area congressional seat in 2008, ran an uninspiring but mistake-free campaign that capitalized on increasing hostility to the Democratic party in Louisiana and throughout the Deep South.

It was the final major race of a 2014 election cycle in which Republicans won nearly every battleground Senate election, gained three governorships and at least 246 House seats. Democrats’ efforts to localize many of these contests fell flat, and Republicans succeeded in making the election a referendum on the unpopular president.

Cassidy, excited as he addressed a throng of supporters in Baton Rouge, wrapped up his speech by yelling “Boom!” — and then making his way off stage to celebrate.

( See full election results from POLITICO's Election Central)

Sen. Jerry Moran (R-Kan.), the outgoing chairman of the National Republican Senatorial Committee, noted that Cassidy will be one of a dozen new Republican senators to take office next month and added that, with his win, “Republicans now control every Senate seat, governor’s mansion and legislative body from the Texas high plains to the Atlantic coast of the Carolinas.”

Obama — and his 39-percent approval rating in the November exit poll — has been an anchor on Landrieu all year. In 2008, Landrieu won a majority on election night — pulling 205,000 more votes than Obama and avoiding a runoff.

But the reputation she cultivated as a moderate was no match for the increasing toxicity of the Obama brand in the state.

During the open primary election last month, Landrieu won just 18 percent of the white vote, according to exit polls, compared to 33 percent six years ago. She got 42 percent overall; since no candidate earned a majority of the vote, the top two finishers went to a runoff.

( Also on POLITICO Magazine: Mary and the Landrieus)

Landrieu, delivering her concession at the Roosevelt Hotel in the Big Easy just an hour after polls closed, received some of the loudest cheers when she mentioned her vote for Obamacare.

“This is something to be proud of, and I’m glad we fought for it,” she said, describing her own record as one of “courage.”

Cassidy, 57, ran a low-profile campaign featuring fewer public events. He made the remarkable decision to spend Wednesday and Thursday in Washington for routine House votes, a reflection of his confidence.

The only debate of the runoff took place Monday and produced nothing close to a game-changing moment. Cassidy was awkward and stiff, while Landrieu tried to gin up controversy over him earning $20,000-a-year to practice medicine at Louisiana State University while collecting his congressional paycheck.

Landrieu found herself on the defensive for improperly billing taxpayers more than $30,000 in private charter flights to campaign events since 2002. But the debate mainly focused on the issues that have defined the contest, such as Obamacare, gun control and abortion. Landrieu is on the wrong side of the state’s electorate on each.

She made two significant strategic miscalculations. First, she thought she could win outright in November and spent accordingly — burning through almost $16 million, more than double what Cassidy spent. Second, she thought control of the Senate could come down to the results in Louisiana, which would guarantee national Democrats spent millions — or maybe tens of millions — on her behalf.

Neither came to pass. Just two days after the first round of voting, the Democratic Senatorial Campaign Committee canceled $1.9 million of advertising reservations it had made to help in the runoff.

Landrieu publicly criticized the party for giving up on her, and she asked female colleagues to try cajoling DSCC leaders to reverse their decision.

The National Republican Senatorial Committee also scaled back its buys after the Democrats pulled out but still spent around $1 million in the runoff. Also spending around $1 million were American Crossroads, Freedom Partners and the National Rifle Association. Ending Spending, the conservative group, spent $1.7 million on TV ads and direct voter contact.

The Republican National Committee said it spent $2.9 million on the ground game, including an effort to test new tactics it wants to try during the 2016 presidential campaign.

The main outside group helping Landrieu on TV during the runoff was the Humane Society Legislative Fund, which spent a paltry $123,000.

In total, outside groups supporting Landrieu aired about 100 TV ads, compared to more than 6,000 commercials from anti-Landrieu groups.

Before the November election, Landrieu’s campaign aggressively reached out to the African-American community, which is about one-third of the electorate. But they did so carefully to avoid linking the senator too closely with Obama.

During the runoff, the campaign became much less cautious. Her chief of staff was caught on hidden camera bragging to a predominantly African-American crowd that his boss votes with Obama 97 percent of the time and would continue to — a statistic already being cited in Republican attack ads.

Also believing the runoff was ultimately a base election, Cassidy focused on winning over conservatives who didn’t vote for him in the first round. The Friday after the election, Cassidy took fellow Republican Rob Maness, who won 14 percent of the vote in the primary, to dinner at Ye Olde College Inn in New Orleans. Maness agreed to endorse Cassidy at a unity rally the following Monday.

The phones were ringing off the hook at Cassidy campaign headquarters with top-flight surrogates, including potential presidential candidates, trying to help so they could claim some credit for an anticipated win. Among those who campaigned on the ground were Sens. Rand Paul (R-Ky.) and Marco Rubio (R-Fla.), along with former Sen. Rick Santorum (R-Pa.), neurologist Ben Carson and Sen.-elect Joni Ernst (R-Iowa). Sen. Ted Cruz (R-Texas) sent fundraising emails, and former Florida Gov. Jeb Bush headlined a high-dollar fundraiser in Washington this week.

Landrieu brought in a handful of lesser-known Senate colleagues. Hillary Clinton hosted a fundraiser for her at the start of this week, but it was in New York City.

Cassidy was not seen as running a strong campaign. If the majority was at stake Saturday, or polls showed the race in play, national Republicans planned to send several operatives to help right the ship.

But there was really no need. Landrieu made a last-ditch bid during the lame duck to demonstrate her clout by passing the Keystone XL pipeline bill. She pushed her colleagues hard and had support from every Republican senator, but she fell short of breaking a filibuster by one vote.

The Landrieu dynasty is not over. Her brother, Mitch, is the fairly popular mayor of New Orleans and may try to run for statewide office in the future. In her concession, Landrieu said “Louisiana will always be worth fighting for” and promised that her family “will continue to do so.”

Indeed, as soon as she finished her speech, Taylor Swift’s hit song “Shake It Off” started blasting through the ballroom.

The Louisiana governorship is opening up next year, as outgoing Gov. Bobby Jindal plots a presidential campaign. GOP Sen. David Vitter is the frontrunner to succeed him, which could create a vacancy when his seat is up for election again in 2016.

Republicans also held onto two Louisiana House seats in runoffs on Saturday in solidly GOP districts. Ralph Abraham won the seat currently held by GOP Rep. Vance McAllister, who finished fourth in last month’s primary following an adultery scandal. In the race for Cassidy’s House seat, Republican Garret Graves beat former Democratic Gov. Edwin Edwards, the colorful, 87-year-old seeking political redemption after felony convictions for corruption.

Cassidy tried to strike a conciliatory tone near the end of his speech, saying he wanted to let those who opposed him know: “I don’t care that you voted for Sen. Landrieu. I am here to serve you too.”

But he also couldn’t help cracking a joke about his outreach efforts. “I did a robocall in Spanish,” he said. “It probably cost me votes.”

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