Fabricio Alvarado, presidential candidate of the National Restoration party (PRN), gestures during a rally after Costa Rica's presidential election in San Jose, Costa Rica February 4, 2018. REUTERS/Juan Carlos Ulate

SAN JOSE (Reuters) - Evangelical Christian Fabricio Alvarado Muñoz maintained his lead in Costa Rica’s second-round presidential race even as his center-left rival narrowed the gap, according to a poll published on Friday.

The controversial religious singer and former journalist has 55.1 percent of voter support ahead of the April 1 election compared with 44.9 percent for former minister Carlos Alvarado Quesada, said a survey by OPol Consultores.

The 10-point difference between the two rivals compared with a 14-point difference in last week’s poll.

The poll of more than 2,200 people was conducted between Feb. 15 and 16, and has margin of error of 2.1 percentage points.

Alvarado Muñoz’s rise on a ticket fiercely opposing gay marriage was helped by the decline of a centrist two-party system that stretched back decades in a country long considered one of the most stable in Latin America.

Muñoz was elected to the national assembly in 2014 as the only federal deputy representing the Christian-backed National Restoration Party (PRN).