Asked during the lone U.S. Senate runoff debate to describe a professional setback, U.S. Sen. Mary Landrieu and U.S. Rep. Bill Cassidy each recalled an early, embarrassing public speaking debacle. Neither response, I suspect, left many viewers surprised.

Face it: Lincoln and Douglas they’re not. Not in style, and not in substance.

That said, Landrieu clearly learned the lesson she cited from her experience as a young legislator, to have her facts and be prepared. Her performance on the trail during the campaign’s homestretch has been focused and pugnacious. She’s been everywhere, eager to bend journalists’ and voters’ ears. It’s a strategy that plays not just to her acquired strengths but to her position in the race, as an underdog trying desperately to shift the conversation away from party politics.

Cassidy seemed to have taken his own lesson from his “total bomb” at an international medical conference: that he’d never talk his way to success. He agreed to just one debate, where Landrieu wanted six, and has avoided the sort of public appearances where he might be questioned. His showing at the debate, broadcast on WAFB, WVUE and other outlets, was decidedly hit and miss. Like Landrieu, Cassidy is following a logical course for someone in his position as the polls’ clear leader: Don’t do or say anything to distract from the partisan advantage he enjoys against the Deep South’s last standing white Democrat in this now solidly Republican state.

None of which has led to a particularly edifying closing discussion.

Landrieu’s final gambit has been to hit Cassidy over questions about his part-time teaching arrangement with LSU and whether he worked the hours he claimed. She’s been relentless, clinging to the issue like the lifeline that she hopes it is, suggesting that subpoenas are coming and that rather than being a doctor for the poor in the charity system, “he was a doctor for himself.”

He’s reacted dismissively, insisting at the debate that he’s answered questions, and shifting the focus to Landrieu’s taxpayer-funded campaign travel, which she attributed to a bookkeeping error. He even played the holier-than-thou card, arguing that he was helping people and asking repeatedly who her trips helped. Never mind that he got paid for whatever work he did, and that if the discrepancies are nothing more than a bookkeeping error — the best-case scenario for him — then he forfeits the right to attack Landrieu for sloppiness.

There have been plenty of other charges and countercharges swirling around in this final week. U.S. Rep. Cedric Richmond, speaking on Landrieu’s behalf, warned that a Cassidy win would lead to the impeachment of President Barack Obama. Sure, Cassidy doesn’t exactly speak of the president with respect, but that scenario’s highly unlikely, and Cassidy would hardly tip the balance.

A group of black conservatives, joined by the state Republican Party, is claiming alarm over a video of Opelousas Mayor Don Cravins Sr., father of Landrieu’s chief of staff, urging Landrieu supporters to vote twice. His rhetoric was probably ill-advised, but he was clearly joking, not inciting voter fraud.

Is anyone else out there suffering from outrage fatigue?

None of this is to say that the candidates aren’t still debating real policy differences.

Between all the attacks, the debate questioners still managed to cover Landrieu’s support for the Affordable Care Act and Cassidy’s opposition, always the biggest point of contention between these two. The candidates aired differences over raising the Social Security eligibility age (he’s for, she’s not), and closing a loophole on background checks for gun sales (she’s for, he’s not). She touted her focus on state issues and independence from her party; Cassidy harped on his go-to charge that she supports the president 97 percent of the time.

It’s just that the substantive debate, at this point, feels all played out. By now, everybody who cares to know where the candidates stand on issues already knows.

So Landrieu’s taking her last stab at changing the dynamic and making the election a referendum on his behavior, not on her party. Cassidy’s doing his best to wait her out, knowing that the winds are solidly behind him.

And we end up pretty much where we started. If it’s about the two candidates, then Landrieu has a shot.

If it’s all about partisanship, Cassidy has the overwhelming advantage. There really isn’t much more to say than that.

Stephanie Grace can be contacted at sgrace@theadvocate.com. Read her blog at blogs.theadvocate.com/gracenotes. Follow her on Twitter, @stephgracenola.