CARACAS, Venezuela (AFP) — Venezuelans headed to the polls this morning in regional elections seen as a crucial test for President Nicolas Maduro and the opposition alike after months of deadly street protests failed to unseat him.

Public opinion surveys predicted that the opposition would win a majority of state governorships despite alleged government efforts to suppress a high turnout through last-minute changes in voting places and other tactics.

An estimated 18 million people are eligible to elect governors to four-year terms in 23 states. Voting got off to a slow start at 6:00 am (1000 GMT) when the country’s more than 13,500 voting stations opened, AFP journalists on the ground reported.

The opposition Democratic Union Roundtable (MUD) coalition called Saturday on Maduro to immediately expel “Nicaraguan advisors” who it said had been brought to Venezuela to carry out electoral fraud.

It said they were specialists in abruptly changing the sites of voting places, “a technique used by the Nicaraguan government to disconcert opposition voters.”

The MUD has cried foul over changes to the locations of 274 polling stations in 16 states from areas where they polled strongly in the 2015 legislative elections.

“If the vote were to be free and fair, the MUD would likely win between 18 and 21 states,” an analysis by the Eurasia Group said.

The vote comes against the backdrop of an International Monetary Fund report in which it sees no end to the economic downturn and suffering of the population.

Venezuela “remains in a full-blown economic, humanitarian, and political crisis with no end in sight,” the Fund said in a report on Latin American economies.

The country’s economy will have contracted by 35 percent by the end of this year from 2014, and the Fund says the country is headed toward hyperinflation when prices soar uncontrollably every day for a long period.

It said shortages are taking a huge toll on the Venezuelan people.

“The main risk to the region relates to the humanitarian crisis and ensuing migration of Venezuelans to neighbouring countries,” it said.

“The number of Venezuelans arriving in Brazilian and Colombian border towns has been rising sharply as the crisis in Venezuela intensifies.”

International powers accuse Maduro of dismantling democracy by taking over state institutions in the wake of an economic collapse caused by a fall in the price of oil, its main source of revenue.

Sunday’s polls are the first contested by the opposition since the legislative elections which gave it a majority in the assembly.

But the MUD finds itself having to lift its own discouraged support base. They have seen Maduro’s hand strengthened after he faced down four months of protests that killed 125 people, forming a Constituent Assembly packed with his own allies and wresting legislative power from the opposition-dominated national assembly.

For Maduro, the polls are an opportunity to counter allegations of dictatorship at home and abroad levelled at him after forming the Constituent Assembly.

Maduro signalled this week that the election would effectively be a vote in support of the assembly, forcing even its staunchest critics in the opposition to recognise it.

He said governors-elect would have to be “sworn-in and subordinate themselves” to the Assembly, on pain of dismissal.

Even if his socialist party suffers heavily at the polls, the elections could still provide a boost for Maduro, analysts said.

“Though the government will probably find a way to diminish the importance of the results, it will initially recognize the outcome as it seeks to revive stalled talks with the opposition and stave off additional sanctions,” the Eurasia analysis said.