Just as he did in previous films like “Election,” “About Schmidt,” “Sideways” and “The Descendants,” Alexander Payne maintains a wonderful balance between sentiment and satire in “Nebraska.” His treatment of Middle American characters struggling with family troubles amid economic distress is gently mocking without becoming condescending, and affectionate without degenerating into schmaltz. The effect, bolstered by exceptional work from the cast and lustrous widescreen black-and-white cinematography by Phedon Papamichael, is almost magical in its mixture of humor and poignancy.

The film is essentially a father-and-son road trip from Montana to Nebraska. Woody Grant (Bruce Dern in a career-capping performance) is a grizzled, half-befuddled old alcoholic who becomes convinced that a sweepstakes mailing that’s nothing more than a typical scam to promote magazine purchases represents an actual award of a million dollars, and he’s determined to get from Billings to Lincoln to claim the prize personally. Though his sharp-tongued wife Kate (hilariously feisty June Squibb) dismisses his obsession as the nuttiness of an old crank, Woody—who can no longer drive—is determined to walk the whole distance if need be, which convinces his son David (sad-faced Will Forte from “Saturday Night Live,” delivering a beautifully restrained performance) to drive him, even though he knows the entire trek is a waste, money-wise.

David is himself a rather pathetic figure—his live-in girlfriend has just moved out and his dreary job as a stereo salesman barely makes ends meet. But he somehow understands the importance of this quest to his bedraggled father and becomes his Sancho Panza in hopes of bonding with the man he’s always felt little connection with. Their trip, of courses, becomes a picaresque filled with little incidents, such as a genial one involving a lost set of dentures.

But the centerpiece is a stopover in Woody’s hometown of Hawthorne, Nebraska, where a visit with his extended family, some of whom have their hands out, and encounters with old acquaintances—notably his erstwhile partner in a garage (Stacy Keach) whom Woody holds responsible for a past grievance but who, conversely, feels he’s entitled to a share in Grant’s winnings, as well as an elderly newspaperwoman (Angela McEwan)—give David new insight into his father’s past. After excursions to the dilapidated Grant homestead and the windswept local cemetery, the journey ends at the dingy sweepstakes headquarters in Lincoln and a final gesture by David that leads to a slow drive down Hawthorne’s main street that’s both melancholy and uplifting, a lovely summing-up of the life of a man not unlike the ones James Agee called famous.

Bob Nelson’s alternately touching, edgy and funny script and Payne’s typically gentle, unforced direction give their cast the opportunity to shine without being rushed. Dern is amazing, utterly jettisoning the hyper style that’s so often been the essence of his personality with a marvelously subtle turn that avoids the invitation to pander to the audience. It recalls Jack Nicholson’s Schmidt, not because the two characters are similar but because under Payne’s light touch both veteran stars perfectly embody their worlds of regret without losing sight of their dignity. Forte matches him beat for beat in an understated performance so good that it almost makes one forgive “MacGruber.” (I said almost.) Squibb, who was Nicholson’s short-lived spouse in “Schmidt,” here gets the chance to please the crowd with her blistering outspokenness, behind which lie hidden reservoirs of affection. Keach alternately exudes false joviality and backwoods menace, while Bob Odenkirk is a fine foil as Woody’s older son, a TV anchorman who’s a big fish in a very small, probably frozen pond. Most of the supporting cast—including McEwan, and Mary Louise Wilson and Rance Howard as Woody’s relatives—all strike the right tone, with the only jarring notes coming from Tim Driscoll and Devin Retray as David’s bumptious cousins, who represent the sole instance in which Nelson and Payne go for the satiric jugular, upsetting the film’s otherwise carefully modulated approach.

And just as important to the success of “Nebraska” are Papamichael’s crystalline cinematography, which gives the locations a luminous purity at odds with their distressed condition, and Mark Orton’s spare score. Though they don’t call attention to themselves, Dennis Washington’s production design, Sandy Veneziano’s art direction, Beauchamp Fontaine’s set decoration and Wendy Chuck’s costume design are all integral to the film’s authentic yet iconic look, too.

To be honest, Nebraska, on the evidence of this film, is hardly a pictorial garden spot one might long to visit. But as Payne and Nelson also show, it is a place filled with the dreams, longings and disappointments of the sort of people mostly overlooked in the great mass of American films. Their “Nebraska” is a destination you should head for without delay.