The triumph of “Little Miss Sunshine” at the Screen Actors Guild Awards Sunday night, where it took the ensemble prize — SAG’s rough equivalent to Oscar’s Best Picture — would seem on the face of it to indicate this VW bus full of lovable losers is heading for the winners circle for the top prize at the Kodak. Last week, the Producers Guild surprised by annointing “Little Miss Sunshine” as their pick. And it was just last year that the same SAG award pointed the actor-heavy academy toward an upset victory by “Crash.”

But history suggests “Sunshine” has to circumvent a major roadblock on the road to a Best Picture Oscar. It crucially lacks a Best Director nod at the Oscars and in modern times only “Driving Miss Daisy” (another automotive title, as it were) crossed the finish line without a Best Director nominee steering it toward victory.

The next major heat for “Little Miss Sunshine” is next Saturday night at the Directors Guild of America, historically the most accurate Oscar bellwether. Unfortunately for prognosticators, only three of their nominees — for “Babel,” “The Departed” and “The Queen” — match up with the Oscars’ Best Director field, with “Dreamgirls” and “Little Miss Sunshine” subbing for the academy equivalents, “Letters from Iwo Jima” and “United 93.” Last year Ang Lee, honored by the DGA for “Brokeback Mountain,” went on to win the Oscar — but the top prize, of course, went to “Crash.” But “Crash” had a Best Director nomination. Go figure.

As for the rest of the SAG awards, they were (yawn, yawn) a re-run of the Golden Globes: Mirren, Whitaker, Hudson and Murphy. Of the four, only Murphy seems to be in trouble at the Oscars, particularly with another smug acceptance speech notably lacking in humility. Look for Alan Arkin of “Little Miss Sunshine” to pass Murphy for Best Supporting Actor before the Oscar ballot deadline of Feb. 20 — if he hasn’t already.