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President Obama "signed off" on the decision to reverse course and overtly encourage support for his affiliated super PAC, Priorities USA Action, senior campaign officials said today.

"It's been an evolving conversation," one official said, explaining the move on a conference call with reporters. "We've been watching throughout the course of the Republican primary process, the most recent filing deadline and the Koch brothers conference and what's been coming out of that:  a half billion dollars to defeat the president."

Aides refused to characterize Obama's feelings on the decision - specifically whether he made it "distastefully" - or when he made it.

"I'm not going to characterize how the president came to the decision. It's pretty clear that the president doesn't support the law as it currently stands, but he realizes this is the law that currently stands," one campaign official said.

Just two days ago, Obama told NBC's Matt Lauer that he "worries" about the influence of super PACs on the political process.

"One of the worries we have obviously in the next campaign is that there are so many of these so-called super PACs, these independent expenditures that are gonna be out there," he said. "There is gonna be just a lot of money floating around, and I guarantee a bunch of it's gonna be negative."

Later Obama defended his role in soliciting campaign contributions from wealthy donors - likely the same crowd that will be now tapped to give to Priorities USA - as an inconvenient reality.

"Unfortunately, right now partly because of Supreme Court rulings and a bunch of decisions out there, it is very hard to get your message out without having some resources," he said.

Then, one day later his campaign announced that his Cabinet secretaries and top White House officials would help raise millions for a super PAC that will run negative ads.

GOP independent political groups have spent more than $40 million on radio and TV ads in the primary campaign so far, with millions more in cash on hand. Billionaire brothers Charles and David Koch have also reportedly pledged to spend close to $100 million in conjunction with dozens of their allies to campaign against Obama.

Officials emphasized that White House and campaign staff would not overtly solicit funds for the super PAC but simply "express support for their mission, which is re-electing the president." The president, vice president and first lady are not expected to attend any super PAC events.