"To put it in marketing terms, McCollum's brand is not well-identified despite a long career of service to Florida," Greg Truax of Tampa, a contributor to the campaign, told The St. Petersburg Times.
McCollum's opponent in the Republican primary, Rick Scott, is making his first bid for elective office. Scott, the former CEO of the healthcare company Columbia/HCA, has spent $15 million of his own money so far, while McCollum raised only $5 million through March.
A recent poll that indicated McCollum trailing Scott by 13 points won't to help the attorney general's fundraising, experts say.
Scott, a lawyer, is also the founder of Conservatives for Patients Rights, which opposes a federal government role in healthcare. Truax said he has also been more in line with conservative views on the "hot-button issue" of immigration reform.
The primary is scheduled Aug. 24.