When a Venezuelan prisoner escaped last year and fled to the United States, the Caracas government called him a fugitive. Raul Diaz Pena had been convicted of helping bomb two diplomatic missions — “a terrorist,” according to President Hugo Chavez.

But when the 36-year-old Diaz Pena arrived in Florida, Rep. Ileana Ros-Lehtinen (R) declared him something else: a hero.

“Raul was able to escape the violent grip of Hugo Chavez,” said Ros-Lehtinen, standing next to Diaz Pena at a news conference in her Miami office. “But countless others remain vulnerable to the whims and abuses of the tyrant in charge in Caracas.”

Ros-Lehtinen’s six-year effort to free a man she considered an innocent political prisoner — despite what the Venezuelan courts ruled — was emblematic of her crusading political style. A tough critic of left-wing governments such as Venezuela’s, she believes U.S. leaders should be a voice for freedom and aggressively call out human rights violations.

As the new chairwoman of the House Foreign Affairs Committee, Ros-Lehtinen now has a high-profile platform for her staunch anti-communism. She is attacking abuses by such countries as North Korea, Cuba and China, and they are, at times, attacking her.

Fidel Castro has called her “la loba feroz” — the big bad wolf — and her appointment has prompted warnings in other leftist Latin American countries that relations with Washington could further sour.

Ros-Lehtinen is unperturbed.

“I take it as a badge of honor that tyrants like Chavez, and [Bolivian leader] Evo Morales and the Castro thugs say bad things about me,” she said in an interview. “That means I’m doing my work and attacking them for their record.”

Ros-Lehtinen, 58, is the senior Republican woman in the House, but a newcomer to the top foreign affairs job, which she got after her party won control of the House.

In many ways, she is the opposite of John F. Kerry, the patrician Democrat who heads the Senate Foreign Relations committee. He is Yale; she is Miami-Dade Community College (though she eventually earned a PhD in education). He is a stiff Yankee; she is warm and earthy, “not afraid of hugging someone who is hurting,” Cuban-American activist Frank Calzon said.

But she is no stranger to bare-knuckle politics. Her husband, attorney Dexter Lehtinen, helped produce the “Swift boat” ads attacking Kerry during his presidential campaign.

Ros-Lehtinen’s political philosophy is grounded in her family’s traumatic flight from Cuba when she was 8. They moved into a two-bedroom house in Miami’s Little Havana, where anti-communist exiles regularly crashed on the living room floor. After a career as an educator and a state lawmaker, Ros-Lehtinen won election to the House in 1989.

“For me, it was very natural to fit in to Congress, fit in to our Foreign Affairs committee, and become a voice for freedom and respect for human rights . . . because that’s how I grew up,” she said.

Ros-Lehtinen continues to loathe Cuba’s Castro; she told a filmmaker in 2006 that she would welcome his assassination. Cuba remains the prism through which she sees the world, said several current and former congressional staff members.

“A government that has said one nice thing about the Cuba regime, they are [seen as] an enemy. There’s no nuance, no subtlety. None,” said a former staffer, who like other aides interviewed for this story spoke on the condition of anonymity to avoid reprisals.

Ros-Lehtinen’s outspoken opposition to repressive governments goes beyond Cuba, however. She is planning to seek tougher sanctions on Iran and North Korea. When Chinese President Hu Jintao clinked glasses at an elegant lunch at the State Department in January, Ros-Lehtinen was blasting him on Capitol Hill as “leader of a repressive regime.”

The Diaz Pena case is another illustration of her fervor. The young man had been sentenced to nine years in prison in the bombing of Colombian and Spanish embassy buildings in Caracas in 2003. According to the Venezuelan government, Diaz Pena was convicted on the basis of testimony from three witnesses and chemical tests on his pickup truck, which found traces of C-4 explosives.

But a Venezuelan lawyer in Miami told Ros-Lehtinen that the prisoner had been implicated by a man who later recanted. The case was marked by irregularities, with Diaz Pena languishing for more than three years in prison before a trial.

Ros-Lehtinen sensed an injustice.

“She said, ‘Leave this to me. I am going to move things in Washington,’ ” said the lawyer, Patricia Andrade. The congresswoman pressed the State Department and Organization of American States to help Diaz Pena.

The U.S. Embassy in Caracas granted him a visa last summer while he was out of jail for the day on a work program, according to a U.S. congressional source briefed on the case. In September, Diaz Pena paid smugglers to take him to a Caribbean island, he told reporters. He then flew to the United States.

The case, however, may not end happily for Diaz Pena. The State Department has since revoked his visa. While the records are private, department spokesman Mark Toner said revocations usually occur when “information comes to light indicating that a visa holder may be inadmissible to the United States or otherwise ineligible for a visa.” Diaz Pena is now seeking political asylum.

While tough on her adversaries, Ros-Lehtinen is well liked by colleagues, known for her friendliness and irreverent sense of humor.

In 2001, for example, Secretary of State Colin L. Powell told lawmakers at a hearing that he had time to answer only a few more “quickies.” Ros-Lehtinen shot back: “My press release will read, ‘Ros-Lehtinen does quickie with Secretary Powell.’ So I am ready.” The chamber cracked up.

If Ros-Lehtinen is known as outgoing, however, her staff is widely regarded as being kept on a tight leash. The congresswoman dismissed widespread reports that they are banned from talking with officials from communist countries. Her spokesman, Brad Goehner, said such decisions “are made on a case-by-case basis” and that the staff had met recently with Chinese officials.

Some former staffers said her employees were so cautious that it hurt their effectiveness. “Mistrust projects itself all around. So nobody can work with anybody,” a former Republican staffer said.

Still, Ros-Lehtinen can point to some significant legislation she helped pass, such as the Iran sanctions bill last year and the 2008 reauthorization of PEPFAR, the global AIDS program.

Ros-Lehtinen is not considered a lockstep conservative, ranking only 70 on the 100-point scale maintained by the American Conservative Union. She has broken with her party on bills benefiting illegal immigrants and gay people — two important groups in her district.

With Democrats holding a majority in the Senate, it is not clear whether Ros-Lehtinen will be able to advance some of her more controversial legislation, such as her bill to make U.N. contributions voluntary. She may be more successful in efforts to cut the State Department’s budget. While past chairmen often protected the department’s funding, she has handed Republican leadership a 20-page list of programs to trim.

“We all want to be Santa. But this is a time for Grinches, because there is just no money,” she said.