The hand-picked candidate of ex-president Evo Morales and former president Carlos Mesa are running neck-and-neck ahead of Bolivia's election in October, according to a poll published Tuesday.

Morales leftist ally Luis Arce and centrist Mesa, president from 2003-2005, both have 23 percent support ahead of the twice-delayed elections, set for October 18.

Right-wing interim president Jeanine Anez is trailing with 12 percent, according to the poll by Mercados y Muestras for the daily Pagine Siete newspaper.

Luis Fernando Camacho, who spearheaded protests that led to Morales' resignation in the wake of his controversial 2019 re-election, has just 6 percent of voter preferences.

The presidential election will go to a second round run-off if the leading candidate fails to win 50 percent of the vote, or 40 percent with a 10-point margin.

Luis Arce (pictured June 2020) is a candidate for the Movement for Socialism party in upcoming presidential elections in Bolivia
Luis Arce (pictured June 2020) is a candidate for the Movement for Socialism party in upcoming presidential elections in Bolivia AFP / Aizar RALDES

In the event of a second round, Mesa would win with 47 percent, with Arce polling at 30 percent, the opinion poll showed.

The poll was carried out in 10 cities earlier this month as Morales supporters set up roadblocks around the country in protest at the repeated election postponements.

Bolivia has been going through a crisis since the October 2019 election, when opposition protesters rejected Morales' claims of victory that would give him a fourth term, claiming widespread fraud.

The president eventually resigned after losing the support of the armed forces and fled to exile in Mexico before taking up residence in neighboring Argentina.

Originally set for May 3, the elections were postponed to September 6 and then October 18 because of the worsening coronavirus epidemic.