The group says it has collected six signatures on a petition and recruited 22 volunteers, but reported no fundraising during its first 10 months of operation. The group's treasurer did not respond to an emailed request for comment.
In Alexandria, Va., a man named Eric Williams said he has fielded "millions" of media inquiries since he set up a Super PAC called Hillary 2016 in February, but he declined to discuss his activities further.
The fundraising activities for such groups, if there have been any, should become somewhat clearer in June, when the next quarterly fundraising reports are supposed to be filed with the FEC.
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Despite such deadlines, potential donors still might have a difficult time figuring out how some Clinton-themed Super PACs spend their money.
For example, a man named Nigel Wallace has failed to file two required fundraising reports since setting up Hillaryclintonsuperpac in January 2013, drawing the threat of legal action from the FEC. He did not respond to a request for comment.
Meanwhile, the founders of a Super PAC called Time for Hillary have a record of financial problems and failed business ventures, according to the Center for Public Integrity, an investigative news outlet. The two people listed as officers for the group did not respond to a request for comment.
Another web site, Hillary.org, solicits donations for an "HRC for President in 2016 Committee." The committee's identification number points to a separate PAC that was shut down by a relative of its founder in 2006. A California phone number listed in the web site's registration records has been disconnected and a contact email appears not to be working.
Dubious fundraising groups aren't unusual in politics, one election-law specialist said.
"There are so many committees with similar names, people parading around looking like candidates that aren't candidates, or political committees that aren't the real deal," said Kenneth Gross, a former FEC lawyer now with Skadden Arps, a Washington law firm.
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The Anti-Clinton Groups
At least five Super PACs have been set up to oppose to a Clinton candidacy.
A group called Stop Hillary PAC raised $274,000 last year and already has crossed swords with pro-Clinton forces.
The group complained to the FEC that Ready For Hillary is violating campaign-finance laws because it rented an email list left over from Clinton's 2008 presidential campaign. That type of activity generally is permitted under federal law as long as the campaign and independent groups do not coordinate their messages.
Another group called Dick Morris' Just Say No To Hillary PAC was set up by a conservative political strategist who once advised Bill Clinton, but who more recently has become a harsh critic of both Clintons. Morris did not respond to a request for comment.
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Because federal law generally prohibits independent political groups from using a candidate's name, most of these groups likely will have to change their name if Clinton decides to run for the presidency, election-law specialists said.
But a Clinton candidacy could give a boost to the already-thriving trade in unauthorized T-shirts, coffee mugs and other trinkets that bear her name.
Online retailer CafePress sold tens of thousands of Clinton-themed items during the first three months of 2014, outpacing sales for every political figure except President Barack Obama, a CafePress spokeswoman said.
Seattle designer Holly Hertzel said she has sold fewer than 100 T-shirts and other items with slogans such as "Hillary 2016," but she expects business to pick up at the end of the year. As a public figure, Clinton is not entitled to a cut of the proceeds from those T-shirt sales or to have commercial control of her image.
Hertzel said she did not feel obligated to share her profits with Clinton.
"The only obligation I feel is that I support her," Hertzel said.