7 things you should know about the surprising candidate who could be Brazil’s next president

When Brazilian presidential candidate Eduardo Campos was killed in a plane crash on Aug. 13, he was trailing the incumbent, Dilma Rousseff, badly in the polls.

But three weeks later, his running mate, Marina Silva, appears poised to beat Rousseff thanks to a solid debate performance and a faltering economy that slid into a recession after two straight quarters of economic contraction. Recent polling data show Silva and Rousseff virtually tied a month before the Oct. 5 election, with the former handily winning a run-off if neither garner more than 50 percent of the vote during the first round.

So who is this woman who might be the next leader of the largest economy in South America? Here are seven things you should know about Silva.

1. She comes from humble beginnings

Silva grew up in a remote village in the western Amazon. As a child, she lived in poverty and, from a very young age, worked long hours in the forest collecting rubber from trees to help support her family. One of 11 children, she endured the loss of three of her siblings as well as her mother who died when she was 15. Silva didn't learn to read until a year after her mother's death when she moved to Rio Branco, the most populous city in Acre state. She eventually received a degree in history from the Federal University of Acre in her mid twenties after working as a maid to make her way through college.

2. Silva has had multiple severe health crises

Her childhood was fraught with illness. She had malaria five times in addition to contracting hepatitis. She also suffered from heavy metal poisoning most likely after being treated for leishmaniasis, a parasitic disease caused by sandfly bites. As a result, she is often described as frail and has trouble tolerating things like alcohol and red meat.

3. She's an evangelical Christian

The twice-married, mother of four once thought she was going to be a nun. And when she first moved to Rio Branco, a convent in the city took her in and taught her to read. But the more Silva studied, the more she became drawn to liberation theology, which seeks to alleviate the social, economic and political injustices experienced by the poor. She is now a devout evangelical Christian, but has endorsed civil unions for same-sex couples.

4. She has a unique ancestral background for politics

Silva is multi-ethnic, making her a rarity among high-level politicians in Brazil. Part native Indian, part Portuguese and part African, she reportedly identifies as "black."

5. She has worked to protect the environment for most of her political career

After getting her university degree, Silva worked with Chico Mendes, a well-regarded environmentalist who launched a rainforest conservation program but was later killed for his advocacy. From 2003 to 2008, she served as the minister of the environment in Brazil during which time she dramatically slowed the deforestation of the Amazon and worked to stop the construction of massive hydro-electric dams that were eventually approved under the next administration. Her devotion to protecting the rainforest earned her the ire of agribusiness, the main opposition to her anti-deforestation campaign. In 2013, Silva tried to launch a new political party called the Sustainability Network, but failed to collect enough signatures to be recognized legally.

6. Silva has run for office before

Four years ago, Silva ran for the presidency as a candidate for the Green Party, a small group focused on sustainable development and social justice. She received 19 million votes, forcing a run-off and effectively coming in third. Rousseff went on to win the election over Jose Serra, a former health minister, by 12 points.

7. Even the business community seems to like her

Silva has adopted most of Campos' pro-business platform. She has called for fiscal discipline, remains committed to keep inflation low and has promised not to tamper with the floating exchange rate. (She has also hinted that she would also give more autonomy to Brazil's central bank.) Her free-market friendliness has been met with approval from business leaders, who so far appear inclined to support anyone who isn't Rousseff.