“What constrains the city from adopting a new millage rate that exceeds the advertised rate is the calendar,” she said.

Even if time was plentiful, it is not clear if Spence-Jones could win the other two votes needed to raise taxes. Moreover, Regalado has promised to veto any increase to the tax rate.

In the latest blow, the $45 million payment is due in January for the city’s share of the PortMiami tunnel dig. The city and Miami-Dade County both chipped in on the project.

The city initially financed its contribution with a $50 million letter of credit from Wachovia Bank. In 2010, city officials converted the letter of credit into a two-year loan with a $45 million balloon payment due in 2013.

The Omni CRA, a special taxing district that uses a portion of property tax revenue to fund redevelopment in the blighted Omni neighborhood, had always intended to pay off the city’s bank loan through a bond issue, said executive director Bockweg.

Last year, the City Commission determined the CRA might face difficulty qualifying to issue its own bond, and voted instead to move forward with a $140 million city bond issue that could pay off the tunnel loan, among other outstanding obligations. But former CFO Larry Spring later scaled back the bond issue to $70 million, leaving the tunnel loan unfunded.

Subsequent attempts to issue a bond were derailed by turnover in the city’s finance department and news that the SEC had launched an investigation into earlier Miami bond issues, Bockweg said.

“We thought it was best that we hold off until the conclusion of the investigation, or until we had an understanding of the outcome,” Bockweg said. “We didn’t know how another bond issue would affect our rates or how it would affect the debt service payments.”

Earlier this summer, the SEC determined Miami had misled investors about the city’s financial health in advance of 2007 and 2009 bond issues, and threatened to impose financial penalties. A separate investigation into bonds used to finance the Marlins ballpark is ongoing.

Bockweg said the CRA must move forward now because the clock is ticking on the loan.

Miami Commissioner Marc Sarnoff, who chairs the CRA, said there is ample time to refinance, complete a bond issue or take the debt to the private equity market — the three options currently under consideration.

“We can get this done in time,” he said.

But observers point to the city’s record of dealing with looming financial problems at the last minute.

Former City Manager Merrett Stierheim said it is time for the mayor and commissioners to “be realistic” about the city’s finances and show some leadership by making tough decisions.

First up: Declaring financial urgency, as the court said they could, despite facing political ramifications.

“It looks like a first-class mess,” he said.

Miami Herald staff writers Douglas Hanks and Charles Rabin contributed to this report.