Speaking with ABC's George Stephanopoulos Thursday, Obama called his 2006 decision "a political vote."
"I think that it's important to understand the vantage point of a Senator versus the vantage point of a president," he said. "When you’re a senator, traditionally what's happened is this is always a lousy vote. Nobody likes to be tagged as having increased the debt limit for the United States by a trillion dollars. As President, you start realizing, 'You know what? We can't play around with this stuff."
"So that was just a example of a new Senator, you know, making what is a political vote as opposed to doing what was important for the country. And I'm the first one to acknowledge it," he said.
Obama also conceded that when the current Senate is faced with the same decision, some members may make the same calculation he did.
"The burden is going to fall a lot on Democrats in the Senate to make this happen, but in both chambers, we’re going to need some votes from the other side," he said.
Congress is likely to take up a debt limit increase measure after it returns in May from a two-week recess. Treasury Secretary Timothy Geithner said this week the United States will reach its current $14.29 trillion borrowing threshold on May 16, but that his department can maneuver some of its payments to buy some time -- probably fewer than two additional months.
Congress has voted to raise the debt limit 75 times since 1962.