Ghana's main opposition party has appealed to the nation's top court to overturn the result of presidential elections won by incumbent President John Mahama.

The New Patriotic Party says it has presented evidence of fraud and irregularities to the Supreme Court from the poll earlier this month. The party says it gathered its data from more than 26,000 polling stations across the country.

According to the official results, Mr. Mahama won 50.7 percent of the vote in a field of eight candidates,

while Nana Akufo-Addo came in second with 47.7 percent. Mr. Mahama needed to win a majority of the votes in order to avoid a run-off.

Election officials allowed some polling stations to reopen for a second day of balloting after technical problems with new biometric voting machines caused long delays. The machines scanned fingerprints to identify registered voters.

International election observers said the elections were free and fair despite logistical issues.

Mr. Mahama is scheduled to be sworn in January 7.

The west African nation has earned a reputation for stability in an often turbulent region because of its recent record of peaceful, democratic transfers of power. Following close elections in 2008, U.S. President Barack Obama called Ghana a “model of democracy in Africa.”

Ghana, a nation of about 25 million people, is also one of Africa's fastest growing economies and is beginning to benefit from commercial oil production that began in 2010. The World Bank expects 8 percent growth for 2012 and 2013.