An estimated 2.4 million people living in California are illegal immigrants.

"A lot of us in the entertainment business are terribly spoiled, and we live in a world where we are overprotected and overpaid," Haggis was quoted as saying. "At the same time, I think we have a duty to give voice to those who perhaps haven't the same access. It's about basic fairness."

Among the other celebrities supporting the campaign are Martin Sheen and his son Emilio Estevez, Alfre Woodard, Danny Glover and musician Jackson Browne.

But there are also opponents, such as Mike Spence, who is leading a campaign to permanently prohibit illegal immigrants from getting driver's licenses.

"I think it's another example of how rich Hollywood elites are out of touch with what's going on in California," Spence was quoted as saying.

"They don't see the impact of immigration unless it's hiring someone to help out with chores around their mansions and they're not in competition with illegal immigrants for jobs."

Editor's note: