Peruvian presidential contender Keiko Fujimori widened her lead over rival Pedro Pablo Kuczynski in an Ipsos poll on Sunday, despite a scandal involving Fujimori's top aide. Fujimori was seen winning 52.6 percent of valid votes in the June 5 run-off election compared to Kuczynski's 47.4 percent, according to the results of a mock voting exercise by Ipsos broadcast on local television show Cuarto Poder. The poll was conducted May 19 and 20, a few days after Univision and Cuarto Poder reported that the secretary general of Fujimori's center-right party, Joaquin Ramirez, was under investigation by the U.S. Drug Enforcement Administration (DEA). A man identified as a DEA informant in the report said he had recorded audio of Ramirez affirming that Ramirez laundered $15 million for Fujimori in 2011. "One would have thought that as a consequence...there would be a spike in mistrust of Keiko Fujimori. That didn't happen," Alfredo Torres, the head of Ipsos in Peru, said on Cuarto Poder. Fujimori, the 40-year-old daughter of imprisoned ex-president Alberto Fujimori, has denied any wrongdoing and portrayed herself as the victim of a smear campaign. Ramirez, who has also denied wrongdoing, offered his resignation letter on Wednesday to keep the scandal from hurting her campaign. The results of the Ipsos survey, which showed Fujimori climbed 2.4 points in a week, were broadcast just before a presidential debate in which she confidently attacked Kuczynski as "elitist" and uncommitted to helping the country's poor. Kuczynski, a 77-year-old former World Bank economist, narrowly moved onto the second-round election after coming in second to Fujimori ahead of a leftist rival. "Kuczynski's plan is made for defending the interests of big businessmen," Fujimori said in her closing comments in the televised debate. "His vision...belongs to the transnational corporation." Kuczynski, who tends to shy away from direct confrontation, pointed to widespread corruption in the 1990-2000 government of Fujimori's father and urged Peruvians to vote for a candidate without any links to drug trafficking. Peru is virtually tied with Colombia as the world's top cocaine producer. "The narco-state is advancing and we have to stop it," Kuczynski said. Fujimori lost her first presidential bid in 2011 to President Ollanta Humala, who cannot run again this year because of term limits. The Ipsos survey of 1,803 people has a 2.3 point margin of error up or down. Some 12 percent of voters were still undecided or planned to cast a spoiled ballot. — Reuters