Aiming to raise public dollars to improve their privately-owned stadium, the Miami Dolphins and team backers have hatched a plan: get state legislators to lift the ceiling on Miami-Dade’s hotel tax and then ask county commissioners to increase the rate of the so-called bed tax.

Backers of the plan, which has been presented to state legislators in recent weeks, say the move would generate millions of dollars for renovations on the Dolphins’ Sun Life Stadium — along with upgrades of the Miami Beach Convention Center.

State law now caps hotel taxes at 6 percent, the amount already assessed in Miami-Dade County. Revenues from the tax levied at Miami-Dade hotels are largely spoken for after county leaders agreed to use public funds to construct a new baseball stadium.

“This is certainly one of the options,” Dolphins lobbyist Ron Book said of the plan to seek an increase of the county’s tourist tax. But Book — who also represents Miami-Dade County as a lobbyist — said other financing proposals are being weighed.

“There is more than one way to skin this cat,” he said.

But winning public funding to enhance a stadium whose primary owner is billionaire real estate developer Stephen Ross remains a tall order — particularly at a time governments are strapped for cash and taxpayers struggle through an economic downturn.

On Tuesday, Miami-Dade County Mayor Carlos Alvarez said he hasn’t been presented with any specific proposals. But the mayor declared his opposition to tax dollars being used for renovations at the Miami Gardens facility.

“I would not be supportive of any public funding for the renovation of the Dolphins’ stadium,” said Alvarez, who said he’s against raising the tourist tax. “Now is not the time.”

Alvarez strongly backed the use of public dollars for the under-construction Florida Marlins stadium in Little Havana, but said Tuesday that this situation is different.

For one, a funding source was available then, unlike now, he said. For another, he said “the Marlins will play 81 homes games a year here for the next 30 years, rather than paying for improvements to compete for one game every four or five years.”

NFL executives, Miami Dolphins officials and stadium supporters contend that Sun Life Stadium needs more than $200 million in renovations if future Super Bowls are to return to South Florida.

The improvements include partially enclosing the stadium with a roof that would shield fans from rain showers and the glaring sun. The proposal calls for new lighting to accommodate high-definition television — which the team must currently install every time it hosts a night game.

And the blueprint includes tearing out the lower bowl of the stadium to add 3,000 prime seats and moving the spectator area closer to the field.

Next week South Florida is set to host its 10th Super Bowl, the most for any region in the country.

But some warn it could be the last if the improvements aren’t made, as NFL owners move the championship game to newer, better-appointed stadiums.

“Doing nothing would be a huge mistake as we would surely watch cities like Dallas, Indianapolis and New Orleans land more Super Bowls,” Rodney Barreto, chairman of the South Florida Super Bowl Host Committee, wrote recently.

Alvarez responded Tuesday by saying: “South Florida in February is a place a lot of people would love to be.”

In recent weeks Dolphins CEO Mike Dee and lobbyist Book have been meeting with state legislators in Tallahassee to discuss the funding proposal.

An effort to rewrite state hotel-tax law could set off a scramble for the millions in extra dollars during a historic budget squeeze.

“Do you know how many people are going to jump on that bandwagon? Museums, performing arts centers, arenas,” said Stuart Blumberg, the recently retired head of the Greater Miami and the Beaches Hotel Association who also co-chairs a city panel on the Miami Beach Convention Center.

On Tuesday, Dee declined to discuss specific proposals, including raising the bed tax, saying he wanted to give time for a new sub-committee formed by the South Florida Super Bowl Host committee to consider improvements to the Dolphins home and ways to pay for it.

The committee, headed by former Dolphin Dick Anderson, is set to hold its first meeting Thursday.

“I think the discussion about funding comes at a later point,” Dee said. “What will take place on Thursday is the opening kickoff. All of us will have to let this subcommittee do its work.”

Yet, time is short.

The reason: presentations to NFL owners to win the chance to host the 2014 Super Bowl come in May. Proponents of a stadium overhaul say plans to update the facility must be in place by then.

“The clock is ticking to show we have some movement,” said Dolphins lobbyist Book. “Certainly we have to have something to show the owners, to show what we are doing to keep the stadium in a position that they find acceptable.”