With the not-so-subtle shape of a stock car under cover just in front of her and spotlights glaring in her face, Danica Patrick feigned drama for an announcement everyone already knew was coming.

"For breaking news that will shock the world ...," she said facetiously on Thursday.

Peeling the lid off the worst-kept secret in auto racing, Patrick ended months of skirting questions about her future by officially declaring her plans to leave IndyCar in 2012 to race a full Nationwide season for JR Motorsports and a part-time Sprint Cup schedule with Stewart-Haas Racing.

One of the most marketable stars in auto racing, Patrick had been rumored to be headed to NASCAR even before she ran her first stock race, the ARCA series event at Daytona in 2010. Even while racing limited Nationwide schedules the past two years for Dale Earnhardt Jr.'s team, Patrick had deflected talk of her leaving IndyCar for the fenders of NASCAR.

That all changed, at least officially, when she signed a contract with GoDaddy.com chairman Bob Parsons in front of TV cameras and a few dozen cheering company employees on Thursday.

"If it was about money, I'd have gone a long time ago," Patrick said from GoDaddy's offices in north Scottsdale. "I just go where my heart tells me, where my gut tells me to go, where I'm enjoying my life the most, where I feel like I can have the most success. I've truly enjoyed my experience in NASCAR, to the point that I want to do it full-time."

Patrick will run most of her races in the lower-tier Nationwide Series with only a handful of Sprint Cup races, but her switch to NASCAR should be a big boost to a sport that's been hurt by a sagging economy and a dip in popularity from its heyday just a few years back.

With her telegenic looks, mass appeal, not to mention racy Super Bowl ads, Patrick brings something that's hard to come by: star power.

"We are pleased Danica Patrick has chosen to race full time in NASCAR in 2012," NASCAR chairman and CEO Brian France said in a statement. "She has demonstrated a strong desire to compete and NASCAR provides the best opportunity to race against the top drivers in the world with the largest and most loyal fan base in motorsports on a week-to-week basis. Danica has shown solid improvement in NASCAR and we believe her decision to run full time in the NASCAR Nationwide Series, with additional races in the NASCAR Sprint Cup Series, will be exciting for our fans and a great challenge for her."

On the other side of the wheel, Patrick's decision leaves a big void in IndyCar.

The series has made some big strides under the direction of CEO Randy Bernard, who has aggressively reshaped the sport with innovative marketing approaches. But for all the successes IndyCar has had, Patrick is still arguably the sport's biggest star — certainly it's most recognizable — and losing her will likely put a dent in the sport's momentum.

"Danica has always been a great ambassador for IndyCar, and there is no doubt she has left a positive impression on our sport," Bernard said in a statement. "She has touched millions of fans and many that were new to motorsports. Danica attracted a fan base that every athlete and sports property in the world would love to have. We should give her a great farewell the rest of this season as she opens a new page in her career and wish her continued success with her new direction."

Patrick has run 20 races in two years with JR Motorsports and has five more on the schedule this season. She plans to run between eight and 10 Sprint Cup races with Stewart-Haas, with an eye on a full season in 2013.

Patrick would like to race at the Daytona 500, though the team hasn't mapped out where she'll start or which races will fill out the schedule this year, and didn't rule out another run at the Indianapolis 500 — even after Andretti Autosport announced it had reached a mutual agreement to part ways with her after the 2011 season.

"We're thrilled with Danica Patrick's decision to join us for the 2012 season and looking forward to seeing her behind the wheel of a NASCAR Nationwide Series car on a consistent basis," said Matt Jauchius, chief marketing and strategy officer for Nationwide Insurance. "Her presence will continue to make our Series stronger and more competitive. She has proven to raise awareness levels of our sport, sponsors and competitors; and that's good for everyone involved."

Patrick will leave IndyCar after a decent run.

She became the first woman to win an IndyCar race at Japan in 2008 and was the first to lead the Indy 500, when she did it in 2005 — the same year she earned the pole at Kansas. Patrick also had a high finish of third at the Brickyard in 2009 on her to way to a career-best fifth in the season standings.

Patrick is currently 12th in the IndyCar standings, with seven top-10 finishes.

"The thing you see in Danica right away is how determined she is to be good at what she does," Stewart-Haas owner Tony Stewart said. "She's very dedicated to taking the time and effort to make the transition from Indy cars to stock cars. She has talent, she has the right mindset, and she has the proper drive and determination. It doesn't matter who it is you're looking for, those are the key attributes that you look for in a driver, and Danica's got them."

Patrick had a sharp learning curve when she first started racing stock cars, but has gained ground this year.

After that first ARCA race at Daytona, she struggled with the nuances of the Nationwide car, her best finish a 19th at Homestead with an average finish of 28th.

Patrick has been much smoother this season, posting three top-10 finishes, with a career-best of fourth at Las Vegas — the best finish by a woman at a national NASCAR race. She's made good progress as a part-time driver and expects to get better with a full-time shot.

"I feel like in the last year, I've really come around much more on the track and the top-10s are happening much more frequently," Patrick said. "I feel like I'm getting it more and more all the time. I still have a lot to learn, that's for sure, but I really feel confident that I can be successful in the future."

There's no turning back now that the secret's officially out.