The Iowa Family Policy Council asked Palin to speak at the Nov. 21 event and has booked a downtown Des Moines sports arena in anticipation of a big turnout.
But Palin spokeswoman Meghan Stapleton didn't sound optimistic, noting the crush of groups seeking the former governor's time and her upcoming tour to promote her new memoir, "Going Rogue."
"This is one of more than 1,000 requests for the governor's time," said Stapleton. "This particular invitation arrived late last week. It is under consideration, as so many are, but will be incredibly difficult to attend with her prearranged book tour under way at that point."
Despite that response, policy council officials said they are moving ahead with fundraising to pay for her appearance.
"There are several organizations involved with what the governor does," said Bryan English, a spokesman for the group. "We did not get a 'no' and because of the time frame we have to continue to plan as if she's coming."
The Iowa group has significant clout among potential Republican presidential candidates because social and religious conservatives dominate GOP politics in the state, where caucuses begin the nominating process.
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