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CHARLOTTE - Mitt Romney requested "several" years of tax returns from his potential running mates, a senior adviser to the candidate said Saturday, suggesting that those considered for the ticket may have been required to reveal more financial documents that the candidate himself.

In a briefing with reporters in Virginia Saturday, senior adviser Beth Myers, who was charged with headed the vice president selection process, declined to specify exactly how many years of tax returns were required, saying only that "several" were requested.

Several, by definition, implies more than two years.

Tim Pawlenty told George Stephanopoulos on "This Week" this morning that he gave "several" years of tax returns to Mitt Romney during the vice presidential vetting process. Pawlenty said he didn't remember the exact number of years. He later said he gave Romney a "bunch" of tax returns.

When pressed about what "several" meant, Pawlenty said "We don't get into the details of the vetting process."

Romney, who has been under intense pressure to release more of his own tax returns by both Democrats and members of his own party, has so far released his 2010 returns and an estimate for his 2011 returns.

The campaign has said that the full 2011 returns will be released sometime before the November election.

When asked why he does not put the criticism to rest and just release more of his tax returns, Romney has said that no matter how many he decided to make public, there will always be a call to give more.

And while Romney's own father, George Romney, released 12 years of tax returns during his bid for the presidency, the candidate today cites Sen. John McCain as the one who set the precedent to release just two years.