By Mayela Armas and Vivian Sequera
CARACAS (Reuters) - Former lawmaker Maria Corina Machado is leading the vote count in the Venezuelan opposition's presidential primary by a huge margin and has claimed victory in the Sunday contest, with final results pending.
The vote to choose a unity opposition candidate to face President Nicolas Maduro in his probable re-election bid next year came amid pledges by the United States to roll back sanctions relief if the government fails to lift bans preventing some opposition figures from holding office.
Machado was tallying 93% of the vote, with just over 26% of ballot boxes counted, the primary's organizing commission said around midnight.
"From tonight we begin a great movement for a great national alliance for the transformation of Venezuela," Machado said at her campaign headquarters.
"Today I received a mandate and I accept with Venezuelans the commitment of making that mandate matter."
The count - delayed by a server blockage - was expected to resume later on Monday. It was unclear when the next results update would be given.
Machado's nearest rival, former lawmaker Carlos Prosperi, had 4.75% of the vote.
Participation in the vote, organized without state help, was more than double what had been expected in some states. Venezuela has about 20 million eligible voters.
Polling places - including in private homes and on street corners - were meant to close at 4 p.m. (2000 GMT), but many remained opened hours later, so those waiting in long lines could vote or so additional ballots could be delivered.
Some of the estimated 3,000 polling locations nationwide had to be moved, according to human rights groups and voters, causing confusion.
Voters also faced transportation problems. Gasoline availability was limited in border states Tachira and Bolivar and public transport in the country's interior was working irregularly, according to Reuters witnesses.
"On Friday we waited in three lines to be able to get gasoline for today and we couldn't," said housewife Melissa Diaz, 39, who arrived at her polling place in eastern Guyana City with a nearly empty tank.
"We've lost a whole day, but even if we had to walk or cycle, we were coming to vote."
MACHADO STILL BARRED FROM OFFICE
Machado, 56, an industrial engineer, has led her rivals by some 40 points in polls.
But Machado, like two former rivals who dropped out of the race, is barred from public office over her support of the sanctions on Maduro's government and would not be able to register for the general election.
The opposition and government this week signed a deal on some election guarantees, including the presence of international observers. The accord allows each side to choose its candidate according to internal rules, but did not retract the election disqualifications.
The United States, which broadly eased Trump-era sanctions on Venezuelan oil and gas and bonds in response to the deal, has said Maduro has until the end of November to begin rescinding the bans and releasing political prisoners and "wrongfully detained" Americans.
Though five people were released, lead government negotiator Jorge Rodriguez confirmed this week that those with disqualifications cannot run in the 2024 contest, set for the second half of the year.
SOME SKEPTICAL OF DEAL
Some in the opposition have said they are skeptical Maduro will follow through on the deal.
The opposition, which says the disqualifications are unlawful, has been reticent to say what it would do if Machado wins the primary but is unable to compete in 2024.
Machado - who says her goal is to remove Maduro in a fair and peaceful vote - has said she would pressure the electoral authorities to let her register. Maduro has not announced that he will seek re-election, but many observers expect him to run.
Others have argued selecting a substitute candidate would be necessary, although whether the often-fractious opposition would accept Machado choosing a replacement remains to be seen.
Ten candidates are competing in the primary, where candidates have pledged to come up with solutions for the country's long economic crisis.
"If you buy diapers you don't buy food, so I buy food and not diapers," said 20-year-old hairdresser Rosimar Gonzalez, who voted in central Maracay with her young son in her arms.
"We have to change presidents."
About 4 million of the 7.7 million Venezuelans migrants who have left their country are estimated to be of voting age and are able to vote at centers in 28 countries.
"I came to vote because I want to hug my grandchildren again, because I want to see my country on the road to freedom before I go," said a teary Armando Cedeno, 100, who voted in the afternoon in Maracaibo.
"I am confident that God will give me that gift."
(This story has been corrected to say the vote count will resume on Monday in paragraph 6)
(Reporting by Mayela Armas and Vivian Sequera in Caracas; Additional reporting by Mariela Nava in Maracaibo, Maria Ramirez in Puerto Ordaz, Mircely Guanipa in Maracay, Tibisay Romero in Valencia and Anggy Polanco in San Cristobal; Writing by Julia Symmes Cobb; Editing by Rod Nickel, Andrea Ricci, Josie Kao and Tom Hogue)