(Reuters) - Peru’s leftist presidential hopeful Veronika Mendoza was seen statistically tied with front-runner Keiko Fujimori if the two women end up in a second-round battle after Sunday’s election, according to an Ipsos poll obtained by Reuters Thursday.

Slideshow ( 2 images )

Mendoza, a 35-year-old lawmaker promising “radical change,” would win 42 percent of votes while center-right Fujimori would get 43 percent in a run-off, according to the survey, the first time they were seen head-to-head in the increasingly likely situation.

The survey, which had a margin of error of 2.3 points, was conducted on April 6 after tens of thousands of Peruvians protested against 40-year-old Fujimori’s candidacy on the anniversary of the day her father, former strongman Alberto Fujimori, ordered the military to shutter congress, 24 years ago.

Fujimori slipped 3 points in the Ipsos poll but remained the clear favorite for the April 10 election, with 37.7 percent of valid votes and a double digit lead over each of her nine rivals.

However, at least 50 percent of votes are needed to win outright and stiff opposition to Fujimori is widely expected to force her into a second-round battle with the runner-up.

Mendoza has surged on promises to ditch Peru’s business-friendly constitution to virtually tie investor-favorite Pedro Pablo Kuczynski for second place in opinion polls - spooking markets that had bet on a fifth straight conservative government in the global minerals exporter.

The Ipsos survey showed Mendoza with 20.1 percent of valid votes in the first-round, while Kuczynski would get 20.3 percent. Those figures excluded 16.4 percent of blank or spoiled ballots.

Remaining undecided voters were mostly poor, rural and female - voters who have opted for Mendoza as election day nears.

However, Mendoza also faces growing resistance from voters wary of upsetting a long stretch of economic growth with unorthodox policies.

The share of Peruvians who said they would “definitely not” vote for Mendoza rose three points to 44 percent, while opposition to Fujimori jumped six points to 51 percent, according to Ipsos.

A Fujimori-Mendoza run-off would be the first in Peru to feature two women.

Kuczynski was seen beating Fujimori by seven points in a second-round election, according to Ipsos.