NOTHING JERRY-BUILT ABOUT `MAGUIRE' : IDEAL CASTING, RESEARCH MAKE COMEDY A PERSONAL TRIUMPH.

Byline: Amy Dawes Daily News Staff Writer

It's all happening pretty fast for Rene Zellweger.

The Texas native, a strawberry blonde with a whisper-soft voice who projects a kind of bubbling sweetness and a winning sincerity, was doing fast-food commercials not long ago to pay her way through college. Then she was landing roles in little-seen independent films. Then she was meeting with Tom Cruise.

``I remember I drove to the studio, got out of my car, and just stood there and laughed and laughed and laughed,'' she says. `` 'Cause I thought, `Tom Cruise is in there waiting for me?' That was FUNNY to me. Then I went inside and managed not to throw up.''

Well, she must have done a little better than that, since she did get the part in the sports-agent comedy ``Jerry Maguire'' opposite Cruise, winning over director Cameron Crowe and producer James L. Brooks despite the studio's clamor for a marquee name.

On Tuesday, Zellweger was named ``best breakthrough performer'' of the year by the National Board of Review of Motion Pictures.

Zellweger plays Dorothy, an accountant with a romantic soul and a 5-year-old son to support who throws caution to the winds after she's smitten with hotheaded, soul-searching agent Jerry Maguire (Cruise).

When Maguire leaves the sports agency in a quixotic quest for a nobler approach to the business he's in, Dorothy is the only employee who'll follow him, and soon they're keeping each other's lives and spirits afloat, and falling in love.

Zellweger, whose tongue-tripping Swiss surname is shortened to ``Z'' by pals, says those love scenes were the toughest part.

``He would profess his love so persuasively,'' she said of Cruise. ``He'd be going, `You complete me, I can't live without you.' And then they'd call `Cut!' and he'd yell, `Bye, Z! See you tomorrow.' And he'd be out of there, and I'd be left, trying to recover.''

Cruise, who was producing ``Mission: Impossible'' at the same time ``Jerry Maguire'' was filming, didn't have a lot of time to hang out between takes, as Zellweger recalls.

Nonetheless, she found working with him a profound experience. ``He has this light around him,'' she says unabashedly, ``like he holds a little piece of the universe in his hands, and he has so much of it that he can afford to give a little bit to each person he encounters.''

That kind of outlook - transplanted straight from the sunny small-town environs of Caty, Texas - is part of what endeared Zellweger to Crowe, says the filmmaker, who wrote and directed ``Singles,'' and ``Say Anything'' and scripted ``Fast Times at Ridgemont High.''

``The reason we hired her is the very reason it works on the screen,'' said Crowe. ``Her quirky good heart is just totally on display. It's all very real to her. She brought a convincing context to Tom's character, and that made it real to me. She takes me places when I watch her.''

Zellweger's performance, based on critical reaction so far, is bound to take her places, too. It's only one of her triumphs this movie season, the other being a co-starring role opposite Vincent D'Onofrio in the Christmas Day release ``The Whole Wide World,'' a Texas-set romance based on the true friendship between a schoolteacher (Zellweger) and pulp fiction writer Robert E. Howard.

``It was the first time anyone believed I could play someone with some intellectual maturity,'' says Zellweger of her casting in ``The Whole Wide World'' by director Dan Ireland. ``I used to get laughed at when I wanted to play grown women, 'cause I looked too young.''

The actress does come across as younger than her 27 years, but looks can be deceiving. A former track and gymnastics athlete who dreamed of Olympic glory before realizing at 19 that ``it wasn't going to happen,'' Zellweger gives the impression of someone who will not be easily trampled by fame.

Asked if her love scenes in ``Jerry Maguire'' had required nudity, Zellweger answers quickly, ``That wasn't the deal. The deal was the heart, not the body.''

``I think it's important to keep a piece of yourself for yourself,'' she says. ``Because if you show people everything, and they think they know everything that you are, how are they going to believe that you're this other character?''

For now, keeping her clothes on may have spared Zellweger the kind of media overkill that greeted fellow Texas newcomer Matthew McConaughey (with whom she appeared in a remake of ``The Texas Chainsaw Massacre'') even before the release of his steamy racial drama ``A Time to Kill.''

But the media is taking notice of her nonetheless, and she's a little nervous about what it all means.

``Don't be putting those curses on me,'' she says gently when a journalist refers to her as ``a movie star.'' ``I guess I'm just a little wary of that word, that movie star word. That's not something that's on my list of things to do.''

You worry, though, that in the glare of the media it won't be long before her indefinable freshness evaporates. Perhaps inadvertently, Zellweger describes her qualities best: ``In `Jerry McGuire,' she says, `Dorothy's character kind of shimmers. Everyone else is like a big bang, and Dorothy is like the shimmer. Do you know what I mean?'' Exactly.

``We are so lucky to have Rene in the movie,'' said Crowe. ``I actually say that all the time.''

A former Rolling Stone magazine writer turned filmmaker, Crowe has always been zealous about research - in his '20s, he went back to high school for almost a year to come up with the material that became the movie script for ``Fast Times at Ridgemont High.''

So it's not too surprising that he spent nearly three years on the research phase of ``Jerry Maguire.''

``It's a way to delay the writing,'' says Crowe self-consciously, ``But it really helped, because it took that long to really know these people, to see beyond their prepared raps, and that made the movie much more personal than the sports-world documentary it might have been.''

Crowe says that top sports agent Lee Steinberg of the Newport Beach firm Steinberg and Moorad was his guide to the behind-the-scenes world of agenting, but was not the model for Cruise's character. ``Jerry Maguire at his peak is not one-hundredth as successful as Lee, but Lee did show me the way these guys have to juggle the lives of these athletes and their entire family trees.''

``I actually saw a lot of the things that are in the movie. I saw a guy saying, `Show me the money,' '' which became one of the themes of the movie.''

``This athlete had a contract negotiation coming up and had come to Palm Desert to be paraded around in front of these owners. He was going to be traded like a side of beef, but he was totally focused, he felt that what he was doing was noble because he was there to support his family.''

``I said, `Why are you here?' and he said, `I'm here because I want them to show me the money. I've been in the game for five years, I've gotten the crap beaten out of me, I've played for less than I deserve, and now I want them to show me the money.' ''

``I didn't know if I was witnessing greed or utter nobility,'' said Crowe, ``but I got a little chill, because I thought, `This is so real, I can't make this up.' When I get that, I know this is what I should be writing about.''

CAPTION(S):

3 Photos

Photo: (1--Cover--Color) All in the game

Newcomer Rene Zellweger goes one-on-one with Tom Cruise in the sports-agent comedy `Jerry Maguire'

(2) Rene Zellweger found working with ``Jerry Maguire'' co-star Tom Cruise a profound experience. ``He has this light around him,'' she says unabashedly.

(3) Zellweger plays an accountant with a romantic soul and a 5-year-old son to support. Her character throws caution to the winds after she's smitten with a hotheaded, soul-searching sports agent.