Ghanaians are choosing who will run one of Africa's most stable democracies as a surge in oil revenues promises to boost development and economic growth.
Ghana has had five elections since military rule ended in 1992, but the stakes are seen as higher than ever in Friday’s vote, as commercial oil production that began in 2010 is set to expand.
President John Dramani Mahama, 54, of the National Democratic Congress (NDC), only took power in July, when his predecessor John Atta Mills died following an illness.
The names of six minor candidates also appear on the presidential ballot and could help force a runoff second-round vote.
His challenger, 68-year-old Nana Akufo-Addo of the New Patriotic Party (NPP), lost by less than one percentage point in 2008, and insists he is poised to reverse that narrow defeat.
Voters will also be electing a new 275-seat parliament in Friday's vote.
The NDC won a narrow edge in seats over the NPP in the 2008 vote.
Analysts say that as Ghana's democracy has deepened, the rivalry between the ruling NDC and challenger NPP has also intensified.
"Mutual loathing may be a good way to describe how the parties view each other," said Emmanuel Gyimah-Boadi, a political science professor at the University of Ghana.
"Both parties have tasted power. They know what comes with power. If you capture the presidency, you control all the machinery of the state and unlike the past, we now have oil. The state coffers will be brimming."
One of the world's newest oil producers, Ghana is also a top exporter of cocoa and gold, with economic growth of 14 per cent in 2011. Eight per cent growth is expected for 2012 and 2013, according to the World Bank.