Apple Inc. said last week it was donating $100,000 to fight the proposed ban on same-sex marriages in California, taking a rare political stand that may win some customers and irk others.

The computer and gadget maker joined Google Inc., Qualcomm Inc. and Pacific Gas & Electric Co. in declaring opposition to Proposition 8, which would define marriage as only between a man and a woman.

"We strongly believe that a person's fundamental rights — including the right to marry — should not be affected by their sexual orientation," an Apple statement said.

Wading into a social issue with a six-figure donation is unusual and risky for a company that sells goods primarily to consumers, according to marketing and corporate governance experts.

Although Apple long pitched itself as a counter-culture brand, products such as the iPod and iPhone have brought it into the mainstream.

James Klein, a designer and writer in Newport Beach, Calif., who uses many Apple products, cheered the company's stance.

"It makes me feel so much better about the company I purchase from," he said.

In a statement, the Cupertino, Calif., company said it saw same-sex marriage as a "civil rights issue" for its employees, not just a political one. Apple added that it had been one of the first California companies to offer equal rights and benefits to its workers' same-sex partners.

So far, the biggest corporate donor to the No on Proposition 8 campaign appears to be PG&E, which gave $250,000 in July. Qualcomm, a San Diego-based maker of wireless chips, gave $5,000 in October.

Google declared its opposition to Proposition 8 in September but has not given a corporate donation to fight the measure. Founders Larry Page and Sergey Brin recently gave $40,000 and $100,000 respectively to the No on Proposition 8 campaign.

"It is extraordinarily rare for companies to do that," said Steve Smith, a campaign consultant for No on 8. "It's a bold step on their part. We've seen companies with strong anti-discrimination workplaces jump into this."