All those sponsorship deals (NASCAR, the monster truck, etc.) do is plant the seed in kids' heads.
Then they go to an airshow/carshow and see the Mustang and/or Challenger, they walk over to check it out, and next thing you know they're talking to the local recruiter. The Marines in the SoCal recruiting district did that with an old Humvee back in the mid-'90s - they gave it a nice paintjob, nice wheels, and a huge system, took it to airshows and carshows, and cleaned up. I don't remember the figures, but they had a measurable increase in contracts signed, and made mission well before the end of the FY.