Caracas, Venezuela (CNN) -- Venezuela's Supreme Court has upheld the country's presidential election results, ruling Wednesday against the opposition candidate's challenge.
The court also rejected a claim disputing President Nicolas Maduro's Venezuelan citizenship -- ending one avenue members of the opposition had pursued to challenge the legitimacy of his presidency.
After the closely watched April election to pick Hugo Chavez's successor, officials said Maduro won 51% of the vote. Maduro, Chavez's political heir, was sworn in as president at an April 19 inauguration ceremony.
Opposition candidate Henrique Capriles Radonski had argued that the results were illegitimate and called for new elections.
In May, the opposition filed a lawsuit contesting the election, presenting what it said was a long list of election irregularities that totaled more than 180 pages.
Maduro has stressed that he won a clear majority of votes in the election and accused Capriles and his supporters of inciting violence.
At a press conference Wednesday, Supreme Court President Gladys Gutierrez said that all the lawsuits filed challenging the election were invalid because they did not present enough proof or documentation, Venezuela's information ministry said in a statement.
In another push to challenge Maduro's presidency, some in the opposition have resorted to a tactic familiar to Americans: questioning the birthplace of the president.
In the Venezuelan version of the "birther" movement, its proponents say Maduro was born in neighboring Colombia and is either a Colombian citizen or a dual citizen, either of which would make him ineligible to be president.
The leaders of the movement took their complaint to Venezuela's Supreme Court, to Colombian authorities and even to the European Union.
Maduro's supporters ignore the question as nonsense, and Maduro has repeatedly said he was born in Caracas. No birth certificate has been produced for Maduro.
CNN en Español's Samuel Santamaria and CNN's Mariano Castillo contributed to this report.