As Newt Gingrich and his allies scramble to raise enough money to compete with Mitt Romney in Florida’s costly GOP primary, they’re relying on political players who carry almost as much ethics baggage as the former Speaker himself.

Gingrich’s Florida finance director has reportedly been questioned in connection with state and federal criminal probes involving alleged campaign finance violations. The top donor to a Gingrich-friendly super PAC runs a casino that also is under federal investigation. And Gingrich’s top fundraising consultant happens to be his daughter.

“He can raise a lot of dollars, and a lot of the dollars have question marks attached to them,” said John Pitney, a professor of American politics at Claremont McKenna College.

Gingrich’s fat Rolodex and history of running lucrative political and consulting operations could help him compete financially with Romney, election analysts say, particularly if his campaign gains momentum. But Gingrich’s fundraising tends to come at a high cost in terms of overhead and controversy.

Gingrich’s choice of scandal-plagued political consultant Esther Nuhfer to be his Florida finance director has raised some eyebrows in state GOP circles. Nuhfer has been interviewed by FBI agents and by criminal investigators in Miami and Tallahassee, according to Florida newspaper accounts, in connection with multiple gambling and campaign finance investigations.

The investigations reportedly focus in part on generous payments that Rep. David Rivera (R-Fla.) made to Nuhfer, his longtime consultant and friend, when he was chairman of the Miami-Dade GOP and when he was advising a Florida casino company seeking slot machine approval. Rivera has denied any wrongdoing and told Roll Call in July that no federal agents have contacted him.

Nuhfer “is not a target” of any investigation, said her attorney, Miami lawyer Eric Padron. “She is not in any way implicated in any wrongdoing. She is not going to get charged.” Nuhfer “has cooperated fully” with investigators, Padron added, but he declined to offer details of any contacts from federal or state officials.

The top donor to the pro-Gingrich super PAC Winning Our Future, casino magnate Sheldon Adelson, is also under scrutiny — and not just because he and his wife have donated $10 million to the PAC. Adelson’s casino, the Las Vegas Sands, is reportedly under investigation by the Securities and Exchange Commission and the Justice Department in connection with anti-bribery statutes. The company has denied any wrongdoing.

Some evangelical voters have voiced concerns about the big gambling money bankrolling the pro-Gingrich effort. The super PAC’s managing director, Gregg Phillips, declined to discuss Adelson, saying: “We don’t ever talk about any specific donors.”

The top fundraiser for the Winning Our Future super PAC is Becky Burkett, formerly the chief rainmaker for a now defunct Gingrich-run 527 known as American Solutions for Winning the Future. Burkett helped make American Solutions the top-grossing political organization of its kind in 2010, with more than $28 million in receipts and expenditures.

But more than half of that money — some $15.6 million — was spent on fundraising, including events, direct mail and telemarketing aimed at collecting money, according to the Center for Responsive Politics.

Gingrich’s campaign, too, is top-heavy with fundraising expenditures, a good chunk of them going to his daughter, Jackie Gingrich Cushman. Her Atlanta-based firm, Cushman Enterprises, has received $34,322 from the Gingrich campaign, according to the most recent public records, making her its top-grossing fundraising vendor. Another campaign vendor is Gingrich Productions, the media production firm whose president is Gingrich’s wife, Callista.

“Newt, Inc., is a family business and always has been — even when the family members were different,” noted Pitney.

Gingrich campaign officials did not respond to emailed requests for comment. Romney has sought to make hay out of Gingrich’s past ethics troubles, releasing an ad declaring that House Minority Leader Nancy Pelosi (Calif.) is prepared to release “secret” and “damaging” information relating to the ethics scandal that cost Gingrich $300,000 and his speakership.

Pelosi has rejected that notion, stating that her Gingrich information is all in the public record.

Thus far, Gingrich and his backers have struggled to even come close to matching Romney dollar for dollar in Florida and elsewhere. Winning Our Future announced plans to spend $6 million in Florida before the Jan. 31 primary, but as of today, media trackers had tallied only $2.5 million in radio and TV expenditures, according to the New York Times.

“We are very aggressively pursuing a strategy that will push us all the way to the nomination,” said Phillips, at Winning Our Future. The super PAC has a comprehensive strategic plan involving TV, radio, email, digital media and voter identification and turnout, he said.

The Gingrich campaign raised $2 million in short order in the days following his South Carolina primary win, thanks in part to a seven-figure Internet “money bomb,” but the campaign’s Florida media buys going into the weekend totaled only about $1 million. Combined spending by the Romney campaign and by the pro-Romney super PAC Restore Our Future, by contrast, has topped $15 million.