May Day protests risk being rough in Venezuela on Monday as it marks one month since deadly clashes erupted in a political crisis with no end in sight.
Protesters took to the streets from April 1 to demand elections after the courts tried to strengthen President Nicolas Maduro's grip on power.
Marches in various cities erupted into clashes between riot police and protesters which have since left 28 people dead, according to public prosecutors.
"We are not going to cool down the street," said senior opposition lawmaker Freddy Guevara, however.
"On May 1 we must show our strength, that we are in the majority and that we want to have our say in elections."
The opposition has accused Maduro of installing a dictatorship.
It blames him for an economic crisis that has sparked food and medicine shortages in the major oil-exporting nation.
Even residents of traditionally pro-Maduro districts have been joining in the protests against him in recent days.
"I have been a month now joining in all the protests because I want my country to be free of this dictatorship," said Yoleida Viloria, 42, a hairdresser from the poor neighborhood of Petare in eastern Caracas.
- Election headache -
The president has vowed to continue the socialist "Bolivarian revolution" launched by his late predecessor Hugo Chavez.
Maduro has rejected opposition calls for general elections before his term ends late next year.
He has said he is willing to hold regional polls that were postponed in December. But the electoral authorities have not set a date.
"Any election in the short term would be a defeat for Chavismo," said Edgard Gutierrez, an analyst with pollster Venebarometro.
But the electoral prospects for the center-right opposition coalition look slim.
Popular Will party leader Leopoldo Lopez is in jail.
Prominent opposition leader Henrique Capriles of the Justice First party has been officially banned from politics by authorities.
Opposition parties are obliged to go through an electoral registration process that could lead to some of them being excluded.
But aside from dangerous street protests, some of them see the prospect of regional elections this year as their only remaining lever for pressuring Maduro.
"We have to win back votes, even though these elections will not resolve the underlying problem," said Miguel Pizarro, an opposition member of the legislature.
"We have to take part and combine the elections with resistance in the street to change the government."
Maduro on Sunday welcomed an offer by Pope Francis of Vatican mediation but opposition leaders rebuffed the overture, insisting that there must be a timetable for general elections.