NEW YORK — Thank heaven for undecided voters. These semi-mythical creatures get to ask the questions at the presidential town-hall debate; they're the targets of the campaign ads that swell TV station coffers, and they also provide sitcoms with a way to tackle the 2012 election. Only a few shows have been brave enough to take on a topic as contentious as Obama vs. Romney, and that's probably just as well, since none of them has managed to create a truly funny election story.

This week's episode of "Last Man Standing," Tim Allen's "mancession" comedy, is a particularly problematic exploration of the electoral process. The show generally strikes a retro tone, with Allen's Mike Baxter longing nostalgically for the days when men were macho and women were a little less uppity, but as the first season developed, I thought it had shed the stereotypes it paraded in the pilot. Unfortunately, in this week's episode, the first of the second season, those clichéd characterizations are back with a vengeance.

"Last Man Standing's" undecided voter is Mike's middle daughter, Mandy, who at 18 is eligible to vote for the first time. In the show's universe, Mandy is the shallow dim bulb of the family. Older sister Kristin, a Obama supporter, is the brains of the bunch, and Eve, the youngest, is a tomboy. Mike is a rabid Romneyite, and his wife, Vanessa, takes full advantage of the secret ballot to keep her political affiliation a mystery. Naturally, then, the plot revolves around Mike's and Kristin's attempts to persuade Mandy to support their man.

The campaign for Mandy's vote is dispiriting, with both sides resorting to tired old clichés. Romney's a flip-flopper who hides his money overseas; Obama was born in Kenya and was a mere community organizer. (I don't think we're supposed to believe that Mike really is a Birther, but he parrots the line anyway.)

I don't expect "Last Man Standing" to be subject to fact check, but the absurdity of Mike's arguments saps any drama there might be in the decision. And they're not funny, either. His line that "the Democrats will tax [your] inheritance and probably use that money to throw gay weddings for illegal aliens" is obviously a joke, but a tired one. (And there's no way a middle-class family like the Baxters + single mother Kristin works as a waitress in a diner — would be liable for the inheritance tax.)

Even worse, the decision about which presidential candidate to support boils down to a matter of loyalty. Mike is as hurt that Mandy doesn't simply take on his beliefs as her own as he is when Eve drafts a member of a team he hates onto her fantasy football roster. The show's failure to think of the election in grander terms makes the episode a bore. When Vanessa proudly points out that they've raised their daughters to be independent thinkers, Mike's response is a sad and whiny "Where did we go wrong?"

"Obama Mama," the Sept. 25 episode of Ryan Murphy and Ali Adler's "The New Normal" made the opposite mistake. It also focused on an attempt to win over an undecided voter — in this case, Goldie, gay couple Bryan and David's surrogate. Since Goldie, like Vanessa Baxter, refused to reveal her voting intentions, her 9-year-old daughter Shania became her proxy. (Surrogacy runs in the family, I guess.) Shania tells Bryan and David, "I was leaning Romney for a while, because he seems more committed to Israel's security, but Obama believes gay people should be treated like human beings, and you guys are gay, so that made me vote for him." An earlier dinner-table debate between the Democratic couple and Goldie's proudly GOP grandmother relied on accurate talking points, but it was a laugh-free snorer of a scene.

This week's "30 Rock," meanwhile, turned the battle for Jenna Maroney's endorsement into a ludicrous exercise in pandering — not unlike the actual presidential campaign. Jenna eventually plumped for Romney because she would be the only cool Republican, and GOP cuts in arts education would mean "our schools would be producing no new actresses, and Jenna Maroney would get all parts." As Salon's Willa Paskin observed, the show didn't have one good thing to say about Mitt Romney, but it couldn't muster much of a case for Obama, either. Instead, it portrayed "the liberal predicament in 2012: disappointment in Obama . . . and horror at the Republican platform," and did so effectively. But the whole thing lacked the series' usual comic zip.

And that's the most disappointing part of these sitcoms' efforts to incorporate the election into their fictional worlds: the political humor fell uniformly flat. Perhaps 22 minutes is just too long for a topical election sketch. In 2016, show runners should take a page out of "The Simpsons' " campaign manual. The Fox stalwart didn't stretch out its campaign jokes over an entire episode; instead it squeezed a bunch of rapid-fire laugh lines into a sub-two-minute spot in which Mr. Burns endorses Mitt Romney. A show that's been around forever showed the young 'uns the most important lesson of campaigning: Make your points quickly, and move on.