Emilio Estevez’s new biopic, “Bobby,” tries once again to resuscitate the myth of Camelot lost. The film ignores the blemishes of assassinated presidential candidate Robert F. Kennedy and is often guilty of the irritating and clichéd writing to which liberal hagiography is susceptible. But strangely, this overly earnest approach has merit. Mr. Estevez may have fallen completely for the Kennedy myth, but by focusing on the people who believed totally in their candidate rather than the policies or effectiveness of the man himself, he has found a use for his hero worship.

The actions and motivations of the Kennedy clan may not always have matched their rhetoric, but they captured an aesthetic of hope with the public. Mr. Estevez’s film re-creates some of RFK’s followers as Hollywood glitterati dressed in the chic 1960s attire and guarded optimism of the period. Beneath the shadow of the Vietnam War, the nation was in turmoil. The civil rights movement was making strides, but the wounds of John F. Kennedy’s death five years earlier and Martin Luther King Jr.’s assassination just two months prior were still raw. The nation yearned for a leader to set them at ease, and for many, RFK was that person.

But Kennedy’s potential to realize those aspirations ended June 6, 1968. Shortly after delivering a speech to celebrate his success in California’s democratic primary, Kennedy was assassinated in the kitchen of the Ambassador Hotel. Mr. Estevez gives only limited access to the candidate through archival footage and recordings of his most stirring speeches. His film has less to say about Kennedy as a candidate than it does about the dreams of his supporters, who were fragile in their optimism and shattered in the wake of his death.

“Bobby” tracks the events of the day leading up to Kennedy’s death through the eyes of people who were at the Ambassador on that suddenly historic day. The action takes place in small vignettes that are often overwhelmed by sentimentality, overseriousness, and undue weightiness. But while Mr. Estevez’s crush on Kennedy creates some problems, he has managed to capture the general excitement of believers in close proximity to their hero.

Mr. Estevez, who wrote, directed, and stars in “Bobby,” has packed his film with familiar faces, cast and carried out to varying degrees of success. Most of the characters are thinly drawn political statements, but the duo that comes closest to overcoming the limits of their characters is William H. Macy and Sharon Stone. They are miscast — Mr. Macy may be many things, though not likely “the most handsome man”Ms. Stone has ever seen — but they make it work. Mr. Macy makes the earnest and conflicted hotel manager appealing, but it is Ms. Stone who creates a touching portrait in his practical, idealist wife.

The trick celebrity casting is often effective but predictable: Heather Graham is a sex kitten, Anthony Hopkins an overly devoted former doorman, and Harry Belafonte his trusty chess partner and retired bellhop.

But most of the recognizable faces are used to clichéd purposes. Laurence Fishburne plays a wizened short-order cook whose blueberry cobbler diffuses racial conflict. Thirty-something Freddy Rodríguez from HBO’s “Six Feet Under” is supposed to pass as the teenage Mexican busboy who was photographed with a dying Kennedy in his final moments. And finally, Lindsay Lohan and Elijah Wood are young ingénues forced to copulate to avoid the Vietnam War.

The most welcome of all the vignettes is the arrival of the increasingly impressive Shia LaBeouf and his screen partner Brian Geraghty, who play slacker campaign volunteers. Unlike most of the characters, these two don’t have a clairvoyant sense of the day’s historic significance. They shirk their duties to visit the cleanest little hippie in town (Ashton Kutcher),who gives them acid and sends them reeling through the afternoon and evening. When the reality of the day’s events hits them, the surprise of wasted opportunity is more powerful than with many of the other characters.

The remainder of the cast is filled out with quirky and often plodding pairings such as the always sunny Martin Sheen trying to comprehend the painfully neurotic Helen Hunt, and Mr. Estevez trying to hold together his alcoholic wife (Demi Moore). Christian Slater, as the hotel’s kitchen manager, represents the lone counterbalance to Kennedy’s optimism — a racist. And even he is transformed by Kennedy’s presence.

Mr. Estevez paints with broad strokes, imbuing nearly every scene with dire importance. If there were fewer stories in the air at any time, the film’s flaws would become more readily problematic, but together they flit back and forth to create an ambience of anticipation that imbues the promise of political change.

Mr. Estevez finds in Kennedy the forebear for the modern liberal movement. He highlights the candidate speaking about the environment (and comically telling schoolchildren that in the near future New Yorkers will have to wear gas masks to breathe), the peace movement, and seemingly uncontrollable acts of violence.

Like any public figure whose life is cut short, the failures that come with age and experience cannot stain Kennedy’s legacy — his hopefulness is suspended in amber. And despite its varied flaws, “Bobby” proves how deeply public figures can affect the lives of private citizens. The director’s politics may be routine and stale, but he gets to the heart of a movement cut down and made bitter. For many people, Kennedy represented the last opportunity to truly change the landscape of American politics. When he was shot, the political optimism of many people died with him.

mkeane@nysun.com