Lula likes to explain the relationships in pragmatic terms, based on Brazil's trade and investment interests. For many critics, however, he's been too tolerant of, perhaps even complacent about, the human-rights abuses and anti-democratic practices occurring under some of those governments.

Lula was criticized for comments he made in March after his last trip to Havana, following the death of Cuban dissident Orlando Zapata Tamayo in a hunger strike.

"I don't think a hunger strike can be used as a pretext for human rights to free people," he told the Associated Press. "Imagine if all the criminals in Sao Paulo entered into hunger strikes to demand freedom."

As Lula prepares to depart, many are asking whether Brazil is ready to be an effective leader, not just in the developing world, but also in addressing tense standoffs as in Iran, where major players see national security interests at stake.

If Rousseff clears the 50 percent hurdle Sunday, she'll have to deal with this mixed legacy.

Government officials, analysts, and Rousseff's public statements suggest she won't make major changes to foreign policy.

Marco Aurelio Garcia, Lula's top foreign adviser and also a main adviser to the Rousseff campaign, told McClatchy in an interview at the presidential palace that she "would maintain the key principles" such as promoting South American integration, increasing alliances with developing countries, and maintaining Brazil's relationship with the U.S.

He also predicted that there'd be stylistic differences, and she'll initially focus more on domestic affairs, Garcia said.

Brazil's foreign policy has been a campaign issue with Rousseff's main challenger Jose Serra criticizing it in several debates.

In one, he said, "Brazil in recent years has allied itself with dictatorial regimes such as Iran, which persecute women and hang dissidents," and are "pursuing an atomic bomb." Rousseff was tortured by her country's military dictatorship.

Some of Brazil's foreign policy initiatives have been adept and highly promising, such as its outreach to African countries and its role turning the G-20 into the main body for discussing global financial policy. Its diversification of markets helped it emerge relatively unscathed from the global financial crisis.

At times, Brazil has even seemed inspired by the Yanqui Imperio.

Antonio Patriota, the Foreign Ministry's second-ranking official, told McClatchy in an interview at the Foreign Ministry that Lula often says: "We have to do like the Americans. They do not neglect any corner of the world. "

Lula's most visible foreign policy initiative was his attempt to draw close to Iran and negotiate in May, along with Turkish Prime Minister Recep Tayyip Erdogan, the lifting of international sanctions against Iran in exchange for a watered-down agreement for Iran to ship nuclear fuel to a third country.

The Obama administration ignored the initiative and pressed on with sanctions at the United Nations Security Council. The Chinese and Russians also were upset and voted with the U.S.

A recent Pew Poll showed that the majority of Brazilians don't share their president's views on how to handle Iran and its nuclear weapons program.

The Lula administration justifies each of its international alliances by saying that cooperation and a refusal to indulge in public shaming are central tenets to its diplomacy.

Analysts also say that the U.S. bears some responsibility for Brazil's moves. Emblematic of his pragmatism, Lula enjoyed warm relations with former President George W. Bush. Just after the 2006 Mar del Plata Summit of Americas, where the U.S. was widely criticized, particularly by Chavez, it was Lula who welcomed Bush in Brasilia.

In his first letter after his health problems forced him to abandon the leadership of Cuba, Fidel Castro lambasted both Bush and Lula for agreeing to an ethanol project.

Paulo Sotero, director of the Brazil Institute at the Woodrow Wilson Center says a combination of factors played a role in accelerating Lula's independent streak. One was the U.S. financial crisis that began in 2008. Many in Brazil "never imagined the U.S. was mismanaging its finances and those of the world." This made them ask: "why should we trust the U.S. and Europe to maintain global stability?"

Subsequently, the Obama administration's botched handling of the Honduras crisis and an agreement with Colombia to support several of its military bases decreased overall confidence in the U.S.

Still, observers question if Brazil's approach is the right one as its stature grows.

Juliette de Rivero of Human Rights Watch in Geneva criticizes Brazil for having abstained in past U.N. Human Rights Commission votes condemning North Korea and the Congo. This year, however, Brazil did vote to condemn North Korea.

De Rivero said that Brazil is clearly developing a new vision on human rights, "and we are fine with that. But it needs to be fine tuned."

She added that "they cannot have a model just based on cooperation," as pressure is sometimes necessary and effective.

Patriota questions the current model assessing human rights, comparing to it credit-rating companies assessing financial markets in the developing world.

He said that, "in human rights, you do not acquire an investment grade then after which you can tell others what to do."

He said that Brazil objects to "selectivity where some countries are demonized and others where similar practices occur are not for political reasons."

As Rouseff wrestles with these issues, should she be elected, she'll start with one advantage. She's already known to Washington, having met President Barack Obama several times, once in the White House.

As the Brazilian chair of the U.S.-Brazilian CEO Forum, she's also met with both Obama and Bush cabinet officials.

At least one U.S. official was impressed by her unusual knowledge of the both presidents Adams (John and John Quincy) after meeting her at the Hay-Adams hotel in Washington.

Her style is also likely to set her apart. While Lula's charisma is hard to match, Rousseff is considered a disciplined intellectual. So she's unlikely to invest so much of her persona in high-stakes foreign policy initiatives. This could help her relate with Obama.