The Florida Republican Party faces a criminal investigation from the IRS, FBI and the US Attorney’s office over party-issued American Express card spending. And among the members of the state GOP implicated is none other than Marco Rubio.

The U.S. Attorney’s Office in Tallahassee, the FBI and the Internal Revenue Service are all involved in the inquiry, which grew out of the state investigation into former House Speaker Ray Sansom. He was indicted on criminal charges that he stashed $6 million in the state budget for an airplane hangar for a friend and campaign donor.

In the federal case, Sansom and others could be charged with making false statements on their tax returns and tax evasion stemming from hundreds of thousands dollars in charges on party credit cards [...]

Meanwhile, in a separate inquiry, the IRS is also looking at the tax records of at least three former party credit card holders — former Florida House Speaker Marco Rubio, ex-state party chairman Jim Greer and ex-party executive director Delmar Johnson — to determine whether they misused their party credit cards for personal expenses, according to a source familiar with the preliminary inquiry.

Political parties, which are tax exempt, are allowed to spend money only on political activities, such as fundraising, running campaigns and registering voters. While it’s commonplace for party officials and politicians to wine and dine donors, the Florida party allowed credit card holders to rack up hundreds of thousands of dollars in charges with little oversight.

At issue is whether or not Rubio used the credit card for personal use without paying taxes on the in-kind income. This builds off a previous report of Rubio’s use of the GOP-issued AmEx card for personal items. The IRS is in the investigation stage and has not pursued a criminal case at this time, but this could presumably result in the IRS billing Rubio for funds owed and possibly criminal charges for tax evasion. For what it’s worth, Rubio’s campaign denied the report.

To be sure, Charlie Crist is at most one step removed from this mess – Jim Greer was a top ally. But Rubio’s direct involvement has to weigh on his chances in the US Senate race. Rubio has a squeaky-clean, rock-ribbed conservative image that, when placed against this lavish personal spending and potential concealment, does not match.

The person who had the best breakfast this morning is clearly Kendrick Meek. The state GOP’s implosion has major implications up and down the ticket for November. A corrupt party under criminal investigation will not be an effective GOTV machine. And of the three potential nominees for the Senate seat, only Meek remains untainted by this scandal.