The academy uses a strange kind of preferential ballot that, for the most part, ignores films listed underneath a voter's top choice. By contrast, the actors', directors', writers' and producers' guilds use a weighted ballot that gives varying points to runners-up depending on their rank when members decide award nominees. The difference between the two voting systems probably accounts for why, for example, only 3 or 4 DGA nominees usually line up with the list of best director contenders at the Oscars.

Here's how the Oscar system works numerically: about 800 academy members must cite a film, actor, writer or director as their number-one choice in order to reap a nomination. There are 5,800 academy members, but only about 80 percent vote. That's 4,640 members. Now accountants say to divide that electorate by one-sixth. The result — 773 — is roughly the magic number of number-one votes needed.

When accountants tally up votes to determine nominees, they stop counting a film's number-one votes once it has reached that number plus one. It automatically becomes one of the five nominees and its ballots are set aside from the rest. If that movie appears at the top of any more ballots, it's ignored. That's when number-two votes finally do matter, and they then count as new number ones. The academy uses this balloting system because it wants to know that behind every nominee is a strong group of voters who really believe that it's the best of the year. It doesn't want any namby-pamby compromising going on.

The Rooting Factor is the single most important thing that Oscar fans need to pay attention to when trying predict top nominees.

Consider, for example, last year. Some Oscar prognosticators may have mistakenly believed that "Kinsey" or "Vera Drake" had a better shot at a best pic nom than "Ray" based upon the superior reviews they received from critics. But, no. "Ray" got the nomination and the other films didn't because "Ray" elicited the same kind of fan response that its subject once did in real life. Oscar voters actually cheered on "Ray" the same way they'd hoot and root for music icon Ray Charles at a concert.

In 2003, "21 Grams" and "American Splendor" received better reviews than "Seabiscuit," but the latter movie was the only one to enter the Oscar derby's lead race because, well, it was a very good and inspiring film about a legendary dark horse that came from behind to win real derbies during the Depression.

So, what movies have the strongest Rooting Factor this year?

Certainly, "Brokeback Mountain" and "Good Night, and Good Luck" have such sizable bases of fanatic support that their nominations are probably secure.

The other three slots are wide open.

"Munich" might make it in. "It has a small, but fierce following," notes USA Today Oscar reporter Scott Bowles. "The question is: is it big enough?"

"King Kong" has lots of crazed followers cheering it on in theaters, too — much to journalists' surprise.

"Before I went to see 'Kong' I didn't consider it to be best picture material," admits Reuters film reporter Bob Tourtellotte. "But after I saw it, it hit me. 'Kong' was the most fun I've had in the theater all year. Maybe it is the best film."

ABC News Radio senior entertainment producer David Blaustein was wowed by the movie, too — particularly its heroine. "Some of the best dialogue from this past year emanated from Naomi Watts' eyes in 'King Kong,'" he says, calling Watts' screen work one of the year's best performances. "Having said that, the odds of her beating Reese Witherspoon or Felicity Huffman are about the same of a 25-foot gorilla slipping and sliding on a frozen lake in Central Park without falling through the ice, then climbing the Empire State Building."

"Kong" failed to impress in one respect. It didn't prove to be as mighty at the box office as expected, which might hurt its chances, but it has wide support in the academy's tech branches. Often that can lift a film into the Oscar high five.

"Crash" didn't get nominated at the Golden Globes, but it's crashing through the guild awards with gusto "because it has such ardent supporters," notes Oscar journalist Pete Hammond. "It's that little, important indie that hung on at the box office against all odds, earning more than $50 million. People are passionate about it — like Oprah. She devoted a whole show to it."

Most Oscar gurus were aware of the secret support for "Crash," so they aren't too surprised by its sudden success at the guild nominations. Less expected was the new burst of support for "Capote." It could do well at the Oscars, too, "because of the hubris of the academy," says Bowles. "They like the idea of getting behind a literary film.

Bowles may have a good point. One surprise among last year's nominees was that "Finding Neverland" made the cut, a fine film about the life of "Peter Pan" author J.M. Barrie that might normally land at number two or three on a snooty filmgoer's ballot, but its literary appeal gave it extra oomph.

"Pride & Prejudice" has literary appeal and passionate devotees too, but Bowles doesn't believe it will be nommed because, "The BBC will be its undoing. As good as the film is, you don't hear anybody saying that it's better than the classic miniseries. That means it's a shadow of what was done before. The academy doesn't vote for second best."

Bowles also dismisses the chances of "Syriana" and "The New World."

"They'll get a lot of number two and number three votes, but not the number ones they need," he adds. "And forget 'Cinderella Man.' Many people are actually rooting against it because they're sick of Russell Crowe."

"Don't rule out 'A History of Violence,'" he adds. "Lots of people are rooting for it and, surprisingly, many are women. They like the movie's message, which is the same one we see in 'Munich.' Violence begets violence and, if you embrace it, you'll be haunted by it."

Bowles is unsure about "Match Point" and "The Constant Gardener." "They both have people rooting for them," he says, "but it's hard to calculate how many."

Hammond agrees that "Match Point" has many boosters and he believes it can be nominated, but he thinks it shares a problem with "Munich": "They both have characters you're not rooting for as a viewer. We have to wonder: how will that affect the films' Oscar chances?"

Another wild card is "Walk the Line." Most pundits predict it'll score a best pic bid based upon Oscar voters' notorious love for musical biopics, which not only lifted "Ray" up to the top race last year, but, surprisingly, "Coal Miner's Daughter" in 1980, too.

"It's a good movie and it's popular," Hammond says, "but it may be vulnerable because you don't hear people saying it's the best film of the year. 'Walk the Line' may not have enough voters rooting for it as their first choice."