Final Score: GOP Gains Nine Senate Seats, Will Hold 54-46 Majority

Saturday's Louisiana runoff election closed the book on the 2014 election cycle (with one small exception noted below); as the dust settles, the GOP achieved a net gain of nine Senate seats, and will command a healthy 54-46 majority in the upper chamber come January. Republicans controlled just 40 Senate seats as recently as early 2010. A few notes on Bill Cassidy's lopsided defeat of Sen. Mary Landrieu, as well as the larger national picture, starting with a look at Cassidy's 56/44 victory margin:

All votes in. #LASen Cassidy 712,330 55.94% Landrieu 561,099 44.06%
— AoSHQ Decision Desk (@AoSHQDD) December 7, 2014

A visualization of Landrieu's downfall, as compared to her last runoff Senate victory a dozen years ago. Change:

Better comparison, perhaps: At left is Landrieu's last runoff win in 2002, by 3 points. At right is tonight's result pic.twitter.com/2JAv1ospLJ
— David Freddoso (@freddoso) December 7, 2014

Landrieu's was a long-held Democratic seat. And I do mean long: 132 years, to be exact. It has now been won by a conservative Republican and medical doctor who's devoted much of his career to treating indigent patients for free. Landrieu has voted 97 percent of the time in favor of the Obama agenda, a statistic confirmed on camera by her chief of staff. Despite her family name, political heritage in the state, and general cockiness, Landrieu was defeated by double digits. Cassidy's victory capped off a banner year for Senate Republicans. Their net jump of nine seats is the largest by either party in any election since 1980, when the GOP netted 12 seats in the Reagan wave. The party also shook an

Obamacare -- which Landrieu supported and has since defended -- was a central issue in this campaign. Now that she's been dispatched, fully half of the 60 Senate Democrats who cast votes for the law in late 2009 will be gone from the legislative body when the new Congress convenes next month, via Phil Klein:

On Dec. 24, 2009, the Democratic-controlled Senate passed President Obama’s healthcare law with a filibuster-proof 60-vote majority, triggering a massive backlash that propelled Republicans to control of the House the following year. On the Senate side, going into this year's midterm elections, 25 senators who voted for Obamacare were already out or not going be part of the new Senate being sworn in next month. After Democratic losses on Nov. 4 and Saturday's defeat of Sen. Mary Landrieu, D-La., the number has risen to 30. In other words, half of the Senators who voted for Obamacare will not be part of the new Senate. To be sure, it isn’t fair to attribute all of the turnover in the chamber to Obamacare...That having been said, many senators who voted for Obamacare lost re-election battles in which they were hit hard for their support for the law and other Democrats were forced to retire because they had no hope of getting re-elected given their support for the law. A total of 16 Senators who voted for Obamacare either failed to win reelection or declined to run for reelection and had their seats turned over to Republicans.

Which is why some Democrats are finally admitting the obvious: Ramming through Obamacare was a critical and costly mistake. The unpopular healthcare may be the single most potent factor in the utter decimation of Southern Democrats, who have been wiped out from the the Atlantic coast to Texas. This statistic is delightful, not just because of Dems' goose egg but because the GOP's tally provides a powerful counterpoint to the Left's preferred "anti-Obama racial animus" explanation:

—> RT @nxthompson: Now official: in the Deep South, black Republicans (1) now outnumber white Democrats (0) in the Senate.
— John Ekdahl (@JohnEkdahl) December 7, 2014

I'll leave you with two statistics from the House side: First, Republicans will now control at least 246 lower chamber seats next year, equaling the party's post-WWII high water mark. If they hang on and win a recount in an Arizona race, they'll hit 247, their highest number since the late 1920's. Taking last night's House runoff results into account, Barack Obama has presided over more midterm losses for his party than any other president in the last six decades. "Make no mistake: these policies are on the ballot. Every single one of them," Obama

famously said in October. Indeed. And voters responded accordingly.