The carrier that services the most Apple (AAPL.O) iPhones in the country has been the last large holdout from offering the text-to-donate fundraising program, which was launched for the first time in U.S. history by President Barack Obama and his Republican challenger Mitt Romney last month.

"We plan to implement this service as soon as possible," AT&T spokesman Michael Balmoris said on Friday.

The program, as it was originally approved, treated political giving the same way as other non-charitable transactions, such as purchases of ring tones, meaning that carriers and aggregators processing the payment were to take a cut that typically ranges from 30 percent to 50 percent of the donated amount.

AT&T had sought to set up a special offer with fee rates that are "substantially less" than regular commercial rates and asked the Federal Election Commission to approve the plan - which the FEC did on Thursday.

"Our customers will now be able to make political donations via text message and the political candidate or committee will receive more of each dollar donated, just as our customers expect," Balmoris said.

Carriers and aggregators do not disclose the rates of fees they charge, but industry sources have indicated that the new rates could mean single-digit percentage charges for text donations, more in line with rates charged by credit card companies for processing online donations.

Text donations are already available to subscribers of Verizon Wireless (VZ.N), Sprint Nextel Corp (S.N) and T-Mobile USA, a unit of Deutsche Telekom AG (DTEGn.DE), among others.

Representatives of Verizon, the largest carrier, and Sprint said they were reviewing the FEC's ruling on Friday and had no immediate decision on when or whether to lower their rates. T-Mobile representatives did not immediately respond.

Thanks to their small size and spontaneity, campaign finance reform advocates and fundraisers have touted text donations as a way to empower small donors in the era of six-figure donations to unlimited-spending outside groups fueling what is likely to be the most expensive U.S. election ever.

With the experience of successful use of texts in raising money for disaster relief and other charity causes - for which carriers do not charge fees - texted political donations could be a lucrative resource in the run-up to the November 6 election.

Obama's campaign has been asking donors to text GIVE to its short donation phone number of 62262 ("OBAMA") on rally signs and TV ads and promoted it at the Democratic National Convention in early September. The Romney campaign, which joined the program a week after Obama, also promotes its number 37377.

Text donations can be made anonymously but have to be capped at $50 per month and $200 in total for one candidate or campaign.

(Editing by Alistair Bell and Lisa Shumaker)

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