A Venezuelan opposition candidate who has been leading in vote count in the governor's race for the home state of the late President Hugo Chávez has been retroactively disqualified by the country's highest court more than a week after the election was held.

The disqualification is likely to raise further doubts about the fairness of Venezuela's electoral system following the first vote in years in which most major political forces agreed to take part and which was monitored by observers from the European Union.

Venezuela's Supreme Court of Justice late Monday ruled that opposition candidate Freddy Superlano should not have been on the Nov. 21 ballot because he had been disqualified over an administrative sanction imposed in August stemming from his work as a legislator between 2015 and 2020.

It ordered the National Electoral Council to set a special election for January.

A preliminary tally by the National Electoral Council showed Superlano with a narrow lead over incumbent Argenis Chávez, brother of the man who founded the ruling socialist movement and who was mentor to current President Nicolás Maduro.

The state has been considered a bastion of Chavismo, and Hugo Chávez's father Adán also had been governor there.

The EU mission's preliminary report said the elections were marred by the use of public funds and other actions to benefit pro-government candidates and by the disqualification of opposition contenders. It said, however, that they had been an improvement over other recent elections.

The regional elections marked the return of major opposition parties to electoral contests, which they had boycotted since 2017, arguing that the country lacks conditions for fair and free elections.

About 8.15 million of the country's 21 million registered voters cast ballots in more than 3,000 contests, including gubernatorial and mayoral races. The opposition lost the overwhelming majority of races.

Ousted candidate Freddy Superlano issued a tweet saying the ruling of the court showed there was "little will to rebuild an electoral route" out of the country political, social and economic crises. He said it effectively nullified "the will of the people."

The court is one of many government bodies seen as loyal to the Maduro government. In past years, it and other agencies have blocked or ruled against major opposition parties and candidates.

The ruling did not explain why the participation of Freddy Superlano was initially authorized while other candidates were kept out of the election.

For supporters of the late president, Barinas, in northwest Venezuela, is considered the birthplace of the country's socialist revolution.

The tight race there "has to lead deeply to political reflection," Freddy Superlano told supporters Tuesday in Caracas, the capital. "In Barinas, after 22 years of the government of the same family, we decided to face what seemed impossible."

Argenis Chávez on Tuesday announced his decision to resign as governor and not run again as the ruling party's candidate. He said the leadership of the United Socialist Party of Venezuela will choose a new contender.

Adolfo Superlano, who filed the court challenge, told reporters that since the beginning of the campaign he had been denouncing serious irregularities regarding the registration of candidates who had a "criminal record and even were administratively disqualified."

He said he asked the court to intervene over "the risk that a disqualified person" could win.

Juan Guaidó, leader of the U.S.-backed faction of the opposition, in a tweet said the court's move exposed Maduro's regime as a "vulgar dictatorship that takes away the will of the people who expressed themselves."

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