Among their number is a geriatric drug addict, an attempted suicide, and a radiantly ordinary child pageant contestant. Add to these a high-on-life optimist, a teenage nihilist, and a mom as the glue who wants this fractured clan to stick together in the pursuit of an elusive American dream.

The Hoovers don't yet know it, but from the opening scene of the tragedy-tinged farce, they will redefine failure and success in winning-is-everything America.

From the opening scenes, when all six gather around the dinner table for a bucket of chicken, it is clear that screenwriter Arndt has composed these exaggerated characters as dissonant temperaments fated to harmonize. This is the scene, despite a plot that strictly adheres to Murphy's Law. And primary-color compositions of the American Southwest reminiscent of a Road Runner cartoon.

To the extent that "Little Miss Sunshine" works, and you probably gather that its schematic cartoonishness didn't always work for me, it is because directors Jonathan Dayton and Valerie Faris genuinely like these people.

So do the actors, especially Alan Arkin as Grandpa, Toni Collette as Mom, Steve Carell as the attempted suicide, and Abigail Breslin as the pint-size pageant contestant, who fully inhabit their characters. Like Frances McDormand, Collette is an actress of such bedrock believability that every time the movie goes over the top, she grounds it with her clear-eyed realism.

Less effective - a problem more of script than of acting - is Greg Kinnear's Richard Hoover, the desperately hopeful creator of a nine-step program called "Refuse to Lose." The screenwriter and directors telegraph their disapproval of anyone who claims to hold the key to success. In so doing, they undermine this character - but not the movie.

Careworn on the Carefree Highway, the Hoovers grind toward California for the date with Olive's destiny.

In a field of blondes who resemble miniature Vegas showgirls, can a pudgy, bespectacled brunette who looks like your average third grader take the crown?