By Patricia Velez
LIMA (Reuters) - The battle for second place in Peru's presidential race has intensified a month before voting as any one of four candidates could squeak through to a likely runoff election against front-runner Alejandro Toledo.
Ollanta Humala, a left-wing ultranationalist, is closing in on two market-friendly candidates who polls show are virtually tied in second place: lawmaker Keiko Fujimori and former Lima Mayor Luis Castaneda.
Humala, who has moderated his tone since unnerving financial markets when he nearly won the 2006 race, has gained about 5 percentage points to 15 percent. Two polls released over the weekend show him only a few points behind Fujimori and Castaneda.
Pedro Pablo Kuczynski, a former Wall Street titan and an ex-prime minister, has also risen to 10 percent as he rolls out an active social media strategy and targets youth voters in one of the world's fastest-growing economies.
"The campaigns of Humala and Kuczynski were catastrophic at the beginning, but it looks like their newer strategies are working," said Manuel Torrado, head of Datum survey firm.
Toledo, a former president and the architect of Peru's free-trade pact with the United States, still leads his nearest rivals by at least 7 percentage points, according to polls from Ipsos Apoyo and Lima's Catholic University.
But he is unlikely to secure the 50 percent of the vote needed to win the presidency in a first-round vote on April 10. A runoff is slated for June 5.
Castaneda, who has been dogged by corruption allegations he has denied, was criticized on Monday by the new mayor of Lima who said her audit of the city's books came up with a laundry list of irregularities.
"Humala has been growing in a sustained way and this support has some projection that could go further," Alfredo Torres, director of the Ipsos poll, said on America TV.
Meanwhile, pollsters said Fujimori might have more support than suggested by polls as some voters could be reluctant to admit they will support a candidate whose father, former President Alberto Fujimori, is now in jail for human rights crimes.
(Reporting by Patricia Velez and Caroline Stauffer; Editing by Terry Wade and Eric Beech)