By Salamander Davoudi, Henry Hamman and Andy Webb-Vidal

Venezuelan opponents of Hugo Chávez think they have found a new ally in their struggle to oust the country's president - Florida's politically powerful Cuban-American community.

Cuban-Americans have their own reason for disliking Mr Chávez: the 53,000 barrels of Venezuelan oil that flow to Cuba daily, which Cuba analysts call a "lifeline" for Mr Castro.

Within the last 10 days, Mr Chávez has agreed to a 68 per cent increase in Mr Castro's oil ration, to 78,000 barrels a day, according to Jaime Suchlicki, director of the Institute of Cuban and Cuban-American Studies at the University of Miami. There were also rumours among Miami Cubans that Mr Castro was being permitted to resell some oil, said Prof Suchlicki.

"It's something that Cuban-Americans think is important," said Joe Garcia, executive director of the Cuban-American National Foundation. "Venezuela is right now the biggest subsidiser of Cuba's economy."

Meanwhile, Mr Chávez, a militaristic populist who considers Mr Castro his political mentor, appears to have strong-armed his way out of an opposition bid to hold a recall referendum and thrown several people in jail.

Opponents of Mr Chávez said last week 18 people had been jailed for political reasons in the past month.

While the Cuban-American community empathises with Venezuelan-Americans, they are concerned for another reason: political strife has prompted an influx of as many as 200,000 Venezuelans into south Florida over the past two years. As Mr Garcia put it, the Venezuelans "are here to stay if conditions stay the way they are in Venezuela now".

Venezuela's political ructions could play a role in November's US elections. John Kerry, the Democratic presidential candidate, strongly criticised Mr Chávez in a statement this month. Pundits saw that as an attempt to compete for Mr Bush's traditional base of support among Cuban-American voters and a signal Mr Kerry would pursue an energetic Latin America policy.

"President Chávez's policies have been detrimental to our interests and those of his neighbours," Mr Kerry said. "His close relationship with Fidel Castro has raised serious questions about his commitment to leading a truly democratic government."

Only two weeks earlier Mr Chávez had praised Mr Kerry and called him a friend.

"The Bush administration has abdicated significant leadership on the issue of democracy in Latin America, especially in Venezuela," said Julia Sweig, deputy director of the Latin America programme at the Council on Foreign Relations think-tank.

A further complication for President George W. Bush is high gasoline prices. Renewed civil strife in Venezuela, the US's fourth-largest supplier, could further disrupt the flow of oil.

Mr Chávez last month threatened to cut off the US's oil supplies if the Bush administration attempted to topple him. Another sharp price rise at the start of the summer travel season would do little for Mr Bush's popularity on the campaign trail.

Perhaps it is little surprise then that support for Mr Bush among potential Hispanic voters, at least in Florida, appears soft.

"It's difficult for Bush to point out one area where his foreign policy is working," said one Cuban-American political strategist. "He said: 'I'm going to be Latin America's best friend,' and there's been a total collapse."

During the presidential election in 2000, Mr Bush won the state of Florida by only 537 votes, even though more than four-fifths of Florida's 500,000 Cuban Americans voted for him.

The strategist said the White House was "searching for Elián", referring to Elián Gonzalez, the Cuban boy whose controversial repatriation by the Clinton administration enraged Cuban-Americans. "They're trying to find some issue that galvanises the Cuban-American community, and they can't. They can't because they've done nothing."

Maylin Silva, a Venezuelan lawyer based in Miami, was one of the organisers of a rally in Miami last weekend that sought to link the Cuban and Venezuelan leaders as sponsors of terrorism. She said she liked Mr Kerry's hard line, adding: "If Kerry wins, it's possible something could change for Venezuela."

If Mr Kerry can convince Cuban-Americans that the road to Havana runs through Caracas, that could prove a speed bump in Mr Bush's drive back to the White House.

Reporting by Henry Hamman in Miami, Andy Webb-Vidal in Caracas and Salamander Davoudi in Washington.