BOGOTA (Reuters) - Leftist former mayor of Bogota Gustavo Petro leads polls ahead of Colombia’s presidential election in May when voters will choose a successor to Juan Manuel Santos, according to a survey on Friday by the National Consulting Center.

Gustavo Petro, Bogota's mayor, answers a question during a Reuters interview in Bogota December 10, 2014. EUTERS/Jose Miguel Gomez

Petro, once a member of the now-defunct M-19 rebel movement and mayor of the capital between 2012 and 2015, had 22 percent support in the poll conducted between Feb. 19 and 21.

A controversial politician, Petro’s 2011 election was seen as proof that politics was the way forward for rebel movements. He was removed from his post by the inspector general for mismanagement of garbage collection and banned from holding office for 15 years, a ruling that was later overturned.

Independent left leaning candidate Sergio Fajardo, a mathematician and former mayor of Medellin, came in behind Petro with 16 percent support. Ivan Duque, who is backed by right-wing former President Alvaro Uribe, was supported by 15 percent of those consulted in the poll.

Duque is not yet the official candidate for the Center Democratic party. He must still participate in a vote to choose a single candidate for a right-wing alliance between Marta Lucia Ramirez, a former defense minister under Uribe, and ex inspector General Alejandro Ordonez.

Former right-wing Vice President German Vargas Lleras came in fourth in the poll with 8 percent. Another 20 percent said they would vote blank in the election.

Rodrigo Londono, former leader of the Marxist guerrilla group the Revolutionary Armed Forces of Colombia (FARC) known by his nom de guerre Timochenko, failed to get any backing in the poll with 0 percent.

The FARC signed a peace accord in late 2016 and has become a political party.

The nascent party, which kept its Spanish acronym FARC by changing its name to the Revolutionary Alternative Common Force (FARC), suspended its campaign two weeks ago after Londono was booed and his convoy attacked with eggs and bottles during tours in the cities of Armenia and Cali.

If none of the candidates get more than half of the valid votes, a second round will be held in June.

The poll interviewed 1,175 people in 35 towns and had a margin of error of 3.8 percen.