When the Pentagon's research arm first called for innovators to design and race a self-driving car to make warfare safer, a ragtag bunch of garage tinkerers, computer geeks and even high school students answered.
No one won the Defense Advanced Research Projects Agency's inaugural contest in 2004.
An encore the following year produced five robots that crossed the finish line, and a team from Stanford University drove away with the $2 million prize.
If yesteryear's contests evoked the Wild West, with teams working in the open desert on a shoestring budget, this year's is modern: The field is more savvy, the terrain is urban and corporate sponsors and public relations machines have entered the fray.
"They've become like NASCAR teams with multiple sponsors and stickers on everything," said Peter Singer, a Brookings Institution senior fellow who has followed the DARPA competitions. "It shows that it's becoming big business."
For the first time, there even will be a sponsors-only section for companies to display their swag next to the pit stop on the grounds of the old George Air Force Base east of Los Angeles on race day, Nov. 3.
The races are part of the Pentagon's effort to fulfill a congressional mandate to have a third of military ground vehicles unmanned by 2015.
The increasing corporate participation points to the reality that money matters in the taxpayer-funded race if competitors are to have any chance of winning.
"Long before the winners receive their checks, they will need support from sponsors to help them compete to win," DARPA said on its Web site.
While corporate sponsorship does not guarantee success, it does help teams offset their costs. Auto makers often donate a vehicle and loan engineers to teams while suppliers offer sensors, cameras and other equipment at discounted prices.
In return, teams stick corporate logos on their race vehicles and publicize them on their Web sites and in promotional brochures.
Sponsors in the first two challenges mostly were bit players. Today, they are more likely to back several teams and in some cases, help lead one.
Part of the reason has to do with new rules that made the contest more lucrative.
Unlike in past years when competitors raised their own money, DARPA gave up to $1 million each to 10 teams in return for the right to use some of the technology that's developed.
Stanford, whose Volkswagen Touareg beat out two vehicles from archrival Carnegie Mellon University last year, received so many sponsorships for the upcoming race that team leaders rejected about a half dozen offers because of a lack of real estate on their latest vehicle, which has the body of a VW Passat.
Stanford was among the richer teams last year with support from big-name sponsors including VW, chip-maker Intel Corp. and energy drink maker Red Bull.
Junior, as the Passat is called, now sports the colorful trademark of Internet search leader Google Inc., one of three new sponsors this year.
Stanford team leader and computer scientist Sebastian Thrun believes corporate involvement has not diluted the competition.
"It still has a strong university flavor," Thrun said.
Google donated $150,000 each to Stanford and Carnegie Mellon universities, which it helped in the past.
"We have our logo on both cars," said Jeff Walz, head of university relations at Google. "We're proud to have that there, but it's not a driving factor."
DARPA chose 35 tricked-out robo-cars to square off in the weeklong semifinals that began Friday in Victorville; 20 will move on to the finals.
This year, computer-controlled cars must pass a driving test in a setting made to look like a city.
Using only its computer brain and sensors, each vehicle must carry out mock supply missions by navigating a 60-mile obstacle course.
The vehicles will be graded on how well they flow with traffic, heed stop signs, maneuver traffic circles and avoid accidents.
The first three robots to complete the mission in less than six hours will win $2 million, $1 million and $500,000, respectively.
DARPA has spent $20.5 million to put on the race. There are no reliable estimates on how much competitors have spent, but teams that received government funding have used up about $1 million, with some spending much more.
The migration of sponsors to the front line doesn't surprise veterans competitors, who say the race has reached a new level. It also reflects the reality that robotics research increasingly involves a collaboration among universities, businesses and the military.
DARPA does not endorse any team or corporate sponsor, but it encourages academia and business to work together.
"It's wonderful to have associates to complement each other. Together you're much greater than the sum of the parts," said William "Red" Whittaker, Carnegie Mellon robotics professor who is competing for the third time.
Carnegie Mellon paired with General Motors Corp. this time around and will enter a converted Chevrolet Tahoe named Boss.
It's the first time the auto maker has had a direct role in the competition. Last year, it supported two teams from Virginia Tech behind the scenes.
Similarly, Autonomous Solutions Inc., which designs and makes unmanned vehicles for the military, sponsored two Florida teams the past two challenges, but broke out on its own this year.
Team leader Paul Lewis said it was easier to persuade the company to get on board after snaring some government funds.
This summer, DARPA released a "sponsorship fact sheet" listing benefits companies can reap, including "corporate and brand positioning as forward-thinking" and "unique environment for delivering key messages."
DARPA director Tony Tether predicted 10 to 15 robots will finish this year's course. He said the concern that the race may become too corporate is valid.
"DARPA only takes things to a certain extent ... we might be approaching that point," he said.
Another team, the Golem Group, started out all volunteers in 2004 with $50,000 that team leader Richard Mason had won on the game show Jeopardy!
With three official sponsors this year, the team and its Toyota Prius is on the smaller side compared to its competitors.
"It is a little bit more upscale, a little less three guys in a garage," Mason said of the current field.
Singer, the Brookings scholar, said the influence of sponsors on the DARPA race remains to be seen.
"Whoever wins, are they going to talk like NASCAR drivers and remember to thank all the key sponsors?" he asked rhetorically.