Running mate replaces Brazil presidential candidate killed in plane crashBy Shasta Darlington, CNNUpdated 5:16 PM ET, Thu August 21, 2014Just WatchedRunning mate replaces plane crash nomineereplayMore Videos ...Running mate replaces plane crash nominee 01:38Story highlightsSocialist Party candidate Eduardo Campos was killed last week in a plane crashHis running mate, Marina Silva, announces she will replace him in the racePolls suggest she has a better chance of beating President Dilma Rousseff A week after the death of Brazilian presidential candidate Eduardo Campos in a plane accident, his running mate Marina Silva announced she would replace him on the ticket, setting the stage for a tighter race.The announcement was widely expected, and a poll released Monday showed that Silva, a well-known environmentalist, had a better chance of defeating President Dilma Rousseff in the Oct. 5 elections than Campos would have.After a lengthy meeting with members of Campos' Brazilian Socialist Party (PSB), Silva, a former senator and environmental minister, was applauded and cheered at a news conference in Brasilia."Without Eduardo we have what always united us: the awareness of where we want to go together," she said.Campos was polling a distant third before his death last Wednesday. Just WatchedBrazilian candidate killed in plane crashreplayMore Videos ...Brazilian candidate killed in plane crash 02:23PLAY VIDEOThe latest figures from the survey group Datafolha showed Rousseff still in the lead with 36% of the vote. But Silva was in second place with 21%, while the center-right candidate Aecio Neves had slipped to third with 20%.That would mean a run-off vote in which, according to the poll, Silva would garner 47% of the ballots, compared with 43% for Rousseff.While the figures likely reflect a sympathy vote following Campos' tragic accident, the numbers are worrying for the governing Workers Party.At the news conference on Wednesday, the PSB also announced that Congressman Beto Albuquerque would be Silva's running mate. Silva unsuccessfully ran for president in 2010 for the country's Green Party.She told the crowd Wednesday that she arrived with "a sense of responsibility, of commitment assumed during the last 10 months of intense work, ready to honor the commitment and go forward with all of those that were building a project with Eduardo."READ: Brazil candidate killed in plane crashCNN Recommends AIRASIA CRASH10 questions about AirAsia tragedyWith the discovery of debris from the AirAsia plane, investigators move closer to discovering what happened. What are the key questions, and what comes next?AirAsia disaster's lasting impactThe growth of AirAsia has been a regional aviation success story. The reason behind the loss of Flight QZ 8501 will be key to whether passengers start to shun it, says Alan Khee-Jin Tan.'Africa is not a country' campaignThey say there are no stupid questions -- but are there? How about, "Do you speak African?"What broke China's Internet in 2014The year of outrage also applies to China's Internet users in 2014.Swimming face-to-face with sharksOne man swims among sharks without the protection of a cage to make studio-quality, intimate photos of the sea creatures.Turning footsteps into free energyUsing a technology that has been around for 130 years, a company called Pavegen hopes to create electricity from everyday human activities.Father of Web predicts next phaseWhat's next for the Internet? Acclaimed scientist and fatherof the World Wide Web Sir Tim Berners-Lee shares his insights.Best Instagram art of 2014Gone are the days of grainy phone images with the resolution of a poor imitation Monet.'Killing will be our religious duty'A chilling video shows Boko Haram executing dozens of non-Muslims. The year in pictures "The year in pictures" treks across the globe, looking back on the events that shaped 2014.Defining Moments: Our changing worldEach day, CNN brings you an image capturing a moment to remember, defining the present in our changing world.Scenes from the fieldBrowse through images from CNN teams around the world that you don't always see on news reports.More from americasReputed boss of Zetas drug cartel captured in MexicoVenezuela gives U.S. 15 days to reduce embassy staffFidel Castro meets with 5 Cuban intelligence agents freed from U.S.