Instead, it's certain to head to a December runoff. With more candidates than the state has seen in at least three decades, the jammed race already is living up — or down — to the stereotypes of the outlandish and oddball Louisiana election.
One candidate, Republican U.S. Rep. Charles Boustany, faces allegations he was a client of prostitutes who were later killed. Republican state Treasurer John Kennedy is accused of promoting suicide because of his oft-repeated catchphrase that he'd "rather drink weed killer" than be a political insider or support the federal health care overhaul.
Another candidate, former Alcohol and Tobacco Control Commissioner Troy Hebert, filmed a 25-minute YouTube video with low-budget effects, donning wigs and costumes to play the major candidates and debate moderators -- male and female -- and draw eyeballs to his struggling campaign.
Meanwhile, former Ku Klux Klan leader David Duke is not only on the ballot, he met the polling benchmark for a televised debate next week.
The seat is open because Republican David Vitter chose not to seek re-election after losing the governor's race last year — partly because of his own 2007 prostitution scandal. Polls show many voters remain undecided, with no candidate pulling away from the pack.
At a suburban New Orleans strip mall, 72-year-old Bob Smith said he was leaning toward one of the Democrats because the GOP had gone "so far to the right."
He was closer to a decision than others.
"It's a guessing game," 58-year-old truck driver Samuel White III, said as he sat outside a driver's license office. "Eeeny-meeny-miny-moe."
Lawyer Ike Ryan, 46, said he tends to vote Republican but hadn't settled on any of the 24 Senate candidates. He's been doing research, he said, "but none of them really stand out to me that much."
"I think the presidential race has sucked all of the oxygen out of the room," he added.
Five candidates are within striking distance of the runoff: Boustany; Kennedy; Democrat Foster Campbell, an elected state utility regulator; Democratic lawyer Caroline Fayard; and Republican U.S. Rep. John Fleming.
All candidates, regardless of party, face each other in Louisiana's primary. If no one exceeds 50 percent support, the top two vote-getters advance to the Dec. 10 runoff.
Lagging in the polls, Duke's campaign has largely been treated as a side-show as he tries to link his candidacy to the popularity of Republican presidential nominee Donald Trump in Louisiana. But the white supremacist Duke surprised political watchers when he reached 5 percent in a recent independent poll, enough to get invited to a Nov. 2 televised debate — which is being filmed at historically black Dillard University in New Orleans.
Kennedy, who has run twice unsuccessfully for a Senate seat, has aired some of the race's more attention-grabbing ads.
In one TV spot, he wraps up by saying: "I believe that love is the answer, but you ought to own a handgun just in case." In another, he delivers his rule for terrorists: "You hit us, we'll hit you back twice as hard. And your buddies. And your goat," before the ad flashes to the close-up of a goat with an assurance that no goats were harmed in the filming.
Boustany replied with an ad starring Meatball the pug, calling Kennedy a "publicity hound" who "races to the cameras with corny soundbites" but without good ideas. Fleming has accused both of his Republican opponents of being engaged in the equivalent of a junior high food fight, while he's the grown-up with the strong conservative ideals.
So far, no one's run an ad on the bombshell and unproven allegation in a recent book that claims Boustany was a client of prostitutes who were later killed. The author cites multiple anonymous sources and does not allege Boustany was involved in the slayings. Boustany has called the allegations "despicable lies." He's suing the author and publisher, and he blamed Kennedy's campaign for spreading falsehoods.
The two major Democrats in the race, Campbell and Fayard, hope to replicate the long-shot victory of Democratic Gov. John Bel Edwards, who defeated Vitter after the Republican was so wounded by his GOP primary opponents that he couldn't recover.
But neither Campbell nor Fayard has been able to consolidate support among Democratic heavyweights and donors, as they promote similar positions like raising the minimum wage and enacting equal pay laws. Campbell touts the endorsement of Edwards, while Fayard has the backing of former U.S. Sen. Mary Landrieu and her brother, New Orleans Mayor Mitch Landrieu.
Associated Press reporter Kevin McGill contributed to this report from New Orleans.