The US has called for electoral reform in Venezuela after supporters of President Hugo Chavez swept all 167 seats in parliament.
Turnout was less than half of that at the last election
Venezuelans showed a "broad lack of confidence in the impartiality and transparency" of the process, the state department said in Washington.
The five main opposition parties boycotted the election, accusing the electoral body of bias.
Only about 25% of registered voters cast a ballot on Sunday.
About 56% turned out in the contested 2000 parliamentary election.
The opposition says the low turnout deprives the election of legitimacy.
Mr Chavez needs a two-thirds majority in parliament to remove the current constitutional limit of two presidential terms in office.
The US has in the past been a harsh critic of Mr Chavez's autocratic style and he in turn has accused America of trying to assassinate him, BBC state department correspondent Jonathan Beale reports.
There were no words of congratulation for Mr Chavez from Washington this week either, our correspondent notes.
Mr Bush's administration continues to see the Venezuelan president and his leftwing rhetoric as a destabilising influence in the region.
Instead, the state department noted the high abstention rate among Venezuelans - though it stopped short of condemning the way the election was held.
It said it would await the report of electoral monitors from both the European Union and the Organisation of American States.
Whatever the final verdict, our correspondent notes, this result will not see an improvement in the poor relations between the two countries.
Empty polling stations
Teodoro Petkoff, editor of opposition-leaning newspaper TalCual, said the vote had "buried" the country's electoral system.
"The government has a problem it cannot ignore - a single-coloured parliament elected amid a gigantic abstention," he added.
Before the final results were announced, officials in the Fifth Republic Movement, Mr Chavez's party, said it had won 114 seats in the 167-seat single-chamber National Assembly while the remainder of seats were apparently won by allies of the president.
Previously, Mr Chavez's supporters held only 89 seats.
The BBC's Greg Morsbach in Caracas says people queued to vote in deprived parts of the city, where support for the president is usually strong.
Polling stations in middle class urban areas were almost empty, our correspondent says.
Mr Chavez condemned the boycott as a Washington-backed plot to destabilise his government.