(CNN) – Marco Rubio's Senate campaign announced Wednesday that 20 of Florida's Republican leaders have penned a letter to Florida Gov. Charlie Crist asking that Crist comply with any donor requests for refunds.
Crist announced last week that he will skip Florida's GOP Senate primary and, instead, run in the general election as a non-party-affiliated candidate. In the wake of Crist's decision, Rubio, the former Florida House Speaker, is expected to nab the GOP nod. GOP primary polls conducted prior to Crist's announcement indicated that Crist, once the favorite, was trailing Rubio by more than 20 percentage points.
Wednesday's letter slams Crist for deciding to abandon the GOP primary.
"As longtime and loyal contributors to Republican causes and your many campaigns, this letter is not easy for us to write," the 20 Republicans say, " But your actions have forced us to take action.
"We are both saddened and disappointed in your decision to abandon the Republican Party during this important election."
They added, "[f]or years we have put our names and credibility on the line by asking our friends to donate to you. Those days are over."
The letter goes on to ask that Crist "return every penny of donor money from every donor who asks for a refund," beginning with the individual contributions to Crist's Senate campaign made by signatories to the letter.
After noting that Crist has campaign war chest estimated at more than $7 million, the letter declares, "Charlie, that is not your money."
The letter ends with a request to all of Crist's Republican supporters to demand that their contributions to his Senate campaign be returned.
CNN has reached out to the Crist campaign for comment. The campaign has not yet responded to CNN's request.
Wednesday's letter is likely the leading edge of a larger effort to obtain refunds from Crist now that he has decided to continue his Senate bid as an independent.
Even before Crist's formal announcement, The Club for Growth, a conservative advocacy group, announced its intention to help Crist donors seek refunds if the Florida governor left the GOP primary.
And, the day after Crist's announcement last week, The Club for Growth slammed the Florida governor.
"Every dollar in Charlie Crist's campaign war chest was dishonestly raised," the group's president Chris Chocola said in a statement.
In anticipation of Crist's announcement, the National Republican Senatorial Committee also said late last month that it would ask for its $10,000 donation to be returned if Crist decided to run as an independent.