Where Are Sarah Palin's Tax Returns? Vice presidential candidate has yet to share her filings.

 -- As election day comes ever nearer, Democrats and open-government advocates are pressing for the GOP vice presidential candidate to release her tax filings, a campaign tradition that extends at least to the post-Watergate era.

Instead, Palin has to date declined to share the documents, becoming part of an ever-more-select historical group of candidates who waited until this late in a campaign year to release their tax filings.

Since 1976, every major-party presidential and vice-presidential candidate has provided that information to the public, according to an analysis by ABC News. Until Palin, only three hopefuls have held onto their tax returns this late:

In 1984, George H.W. Bush, then the Republican presidential candidate, held onto his tax returns until Oct. 3. Bush said he had set up "the biggest blind trust possible" to prevent conflicts of interest, and said he was concerned releasing information on the trust's holdings would violate its terms. He relented under pressure and after receiving assurances from government ethics experts.

In 2000, then-White House hopeful George W. Bush released his tax returns on Oct. 21. He had received two extensions from the IRS, and did not file his returns until Oct. 15.

Also in 2000, Democratic vice presidential candidate Joe Lieberman waited until Sept. 22 to release his tax returns. When he did so, he released only summary information on income, assets and taxes that was characterized in news reports as "bare bones."

"Voters deserve to know as much as they can about the candidates who are asking for their vote," said Massie Ritsch of OpenSecrets.org, a Washington, D.C.-based watchdog focused on politics and money.

Last week the Obama-Biden campaign released 10 years' worth of tax returns for Sen. Joseph Biden, D-Del., in a move intended to pressure the McCain-Palin camp to do the same for Palin, currently governor of Alaska.

A spokesman for Palin Thursday reiterated the campaign's stance on the matter. "We plan to release Governor Palin's tax returns well before the election," said Taylor Griffin.

For Ritsch, that's not good enough. "A campaign that is touting what it will do to make government more transparent can take a first step by making the candidates transparent." Nicholas Tucker contributed to this report.

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