Billionaire Oprah Winfrey is making a million-dollar contribution to Barack Obama’s presidential campaign. And despite all the campaign finance restrictions of the past 30 years, it’s perfectly legal. That’s because Oprah is making her contribution in the form of time on her television show, appearances with him on the campaign trail, and other uses of her celebrity. But if a rival media mogul, someone like Sumner Redstone or John Malone, wanted to make a contribution of more than $2,300 to a presidential candidate, that would be illegal. Because, you know, it’s corrupt to make a large contribution. Wouldn’t want the next president to be indebted to a businessman who gave him a $10,000 contribution.

This Saturday, “Winfrey will host her first-ever presidential fundraising affair on the grounds of the Promised Land, her 42-acre ocean- and mountain-view estate in Montecito, Calif. — an event that is expected to raise more than $3 million for Obama’s campaign.”

Matthew Mosk of the Washington Post outlines some of the other ways Winfrey might help her preferred candidate.

Among the weapons in Winfrey’s arsenal: the television program that reaches 8.4 million viewers each weekday afternoon, according to the most recent Nielsen numbers. Her Web site reaches 2.3 unique viewers each month, “O, the Oprah Magazine,” has a circulation of 2 million, she circulates a weekly newsletter to 420,000 fans and 360,000 people have subscribed to her Web site for daily “Oprah Alerts” by e-mail.

More than that, though, the Nielsen tracking data show that her most loyal viewers are women between 25 and 55 — a group that also votes in large numbers in Democratic primaries.

Oprah’s well aware of her power:

The fundraiser may be only the start. The Winfrey and Obama machines have maintained silence on the exact nature of their talks over what her role will be, but the idea of her appearing in television ads and other appeals is very much in play. She offered during a recent interview with CNN’s Larry King: “My money isn’t going to make any difference. My value to him — my support of him — is probably worth more than any other check that I could write.”…

Winfrey said in an audio Web chat last week that, this year, the Obamas will be her only political guests.

Campaign finance reform was promised as a way to make everyone equal in the political process, to squeeze out the power of big money. But one of its effects is to make some rich people more equal than others. If Oprah–or Rupert Murdoch, or Donald Graham–decides to use his or her resources to help a particular candidate, that’s legal and very powerful. But the rich man who runs a software company is forbidden to use any significant part of his financial resources to help a candidate.

All power to journalists and celebrities in the reformed political process.