ABC’s Shushannah Walshe and Sheila Marikar report:

Two days before Sarah Palin’s much anticipated, on, off, and on again Iowa speech, details are emerging about what the former Alaska governor will say.

A source close to Palin told ABC News that she’ll offer a “full throated defense of the tea party.”

“Regardless of what she decides to do, this rally is for the tea party to kick off this campaign,” the source said, “this” being the 2012 presidential campaign.

ABC News has also learned that Palin’s speech will reference themes from an Aug. 8 Facebook post called “Conquering the Storm.” It discusses the Standard & Poor’s downgrade of the nation’s credit rating and her solutions to the country’s financial woes.

A source close to Palin told ABC News last week that her speech at Saturday’s “Restoring America” event will be a substantive, big-picture vision of America. Palin herself alluded to what she’ll discuss on Aug. 25, when she tweeted a link to a YouTube video entitled “Obama Lies 7 Times In Under 2 Minutes!” and wrote, “I’ll be talking about this and more on September 3rd.”

Palin is slated to be the last speaker at the Tea Party of America’s Saturday rally, which will also feature the likes of Iowa Tea Party chairman Ryan Rhodes, radio host Tony Katz and Los Angeles-based comedian Eric Golub.

Despite confirming her appearance at the rally on Wednesday after putting her participation in the event on hold, all is still not well between the rally’s organizers and Palin’s political action committee. A source close to SarahPAC told ABC News that her team is upset about how the Tea Party of America seemed to hype the event based on the chance Palin would announce her 2012 intentions at the rally.

Palin to Meet Supporters Ahead of Saturday Rally

ABC News has also learned that ahead of her speech, Palin will attend a Conservatives4Palin meet-up in Urbandale, Iowa, on Friday evening. It will be the first time Palin has attended a meeting of the independent group of supporters, many of whom are traveling from across the country to hear her speak.

Conservatives4Palin was started by Palin’s current aide and speechwriter, Rebecca Mansour. Many of the group’s members are also trying to build a grassroots base for Palin through the group Organize4Palin.

ABC News’ John Berman contributed to this report.