During the 2004 presidential campaign, Republicans demanded "disclosure and transparency" in the form of Theresa Heinz Kerry's tax returns.

The Democratic candidate's spouse's hesitance to make her personal financial information public in 2004 spurred hand wringing in the media and condemnation from the right. This year, the shoe is on the other foot, as Democrats Barack Obama and Hillary Clinton have made public their joint tax filings -- including information on their spouses earnings, while Republican John McCain has released only his personal tax returns, refusing to make public the separate filings of his wife.

Voters left in the dark about Cindy McCain's massive fortune -- estimated to be in the neighborhood of $100 million -- will stay that way, she says, even if she goes on to become first lady.

"You know, my husband and I have been married 28 years, and we have filed separate tax returns for 28 years," she said in an interview on NBC's Today Show Thursday. "This is a privacy issue. My husband is the candidate."

Asked if she would release her tax returns if she was first lady, Cindy McCain said: "No."

Cindy McCain is an heiress to her father's stake in Hensley & Co., one of the nation's largest beer distributors. Her fortune helped fuel McCain's rise in politics, and he has frequently used her private jet at little cost, exploiting a loophole in campaign finance legislation passed last year.

While Theresa Heinz Kerry eventually released some of her tax records late in the 2004 campaign, Cindy McCain seems determined to avoid even minimal disclosures.

John McCain released his tax return last month, reporting he had a total income of $405,409 in 2007 and paid $84,460 in federal income taxes.

Democratic National Committee Chairman Howard Dean blasted McCain over his wife's failure to disclose her tax returns.

"What is John McCain trying to hide? Throughout this campaign, he has acted like his own calls for openness and accountability apply to everyone but himself. Now he thinks he can bring that same double standard to the White House," Dean said in a statement Thursday. "John McCain may not like it, but the American people have a right to know about the well documented links between his political career and the McCains' business ventures."

This video is from NBC's Today Show, broadcast May 8, 2008.

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