SANTIAGO (Reuters) - Former Chilean president Sebastian Pinera and independent center-left Senator Alejandro Guillier have established themselves as the favorites to face off in the presidential election in November, two new polls showed on Thursday.


Twenty-nine percent of respondents said they would vote for Pinera, a conservative billionaire, if the election was held on the following Sunday, while 26 percent favored journalist-turned-politician Guillier, a poll run by Gfk Adimark said.


"Pinera and Guillier increased their position by 5 points with respect to last month, and the gap between them remained the same," the pollster said.


Both men are widely expected to announce their presidential bids in the coming months.


The three-point spread between them is equivalent to the margin of error of the poll, which surveyed 1,052 people from Dec. 2 to Dec. 28.

All other politicians who the respondents mentioned trailed by at least 20 points.

Pollster CEP published a separate survey later on Thursday that also showed Pinera and Guillier as the front-runners for the presidential election, which will be held in conjunction with general elections in the country.

According to the CEP poll, which was conducted in November and December, 20 percent of respondents said they would like Pinera to be the next president, up from 14 percent in the previous survey in July and August. Fourteen percent said they preferred Guillier, a big jump from 1 percent.

Guillier was a relative unknown in Chile until recently, but far-reaching money-in-politics graft scandals as well as a sluggish economy have boosted the prospects of political outsiders.

Another recent poll showed Guillier winning a second round by five points against Pinera if neither received the 50 percent of the votes needed to avoid a runoff.

(Reporting by Anthony Esposito; Editing by Lisa Von Ahn and Paul Simao)