As Ghana gears up for the second round of its presidential election Sunday, tension is growing in the camps of the two competitors even as fatigue sets in with the electorate.

A runoff became necessary after no candidate in the first run Dec. 7 round managed to win over 50%.

Sunday's vote will pit Nana Akufo-Addo, a 64-year-old lawyer running for the ruling New Patriotic Party, or NPP, against John Atta-Mills, a law professor and also 64, of the opposition National Democratic Congress, or NDC.

In the first round, Akufo-Addo won 49.1% of the vote, ahead of Atta-Mills with 47.9%, according to the electoral commission.

But the NDC won most seats in the parliamentary contest, held the same day, securing 113 seats against the ruling party's 109. The rest of the 230 seats went to minority parties and independents.

"Now that it's really close, everybody feels they deserve to win. One can see the desperation," said Kojo Asante, legal and governance program officer with the Center for Democratic Development.

"The slant has completely changed, there are (personality) attacks, accusations and counteraccusations, rigging and intelligence reports - left right and center - all over," he said.

The NDC has accused the NPP of using the early voting exercise Tuesday - when members of the security forces and electoral commission officials who will be unable to vote Sunday were allowed to cast their ballots - to rig the election.

The party said significantly more people voted in the early voting exercise for the second round than for the first.

Tension in political circles hasn't spilled over into the electorate, with many voters more interested in Christmas festivities than in the second round, analysts said.

"We don't have the kind of high-pitched mood as in the first round, people are quite relaxed. The only ones on edge are the candidates and their activists," said Emmanuel Akwetey, executive director of the Institute for Democratic Governance, a non-government group.

"It's not only the election preoccupying the electorate, but the festive season. There is divided attention. There is fatigue," he continued.

The same analysts are saying the poll is still too close to call.

"It's still very open ended. One thing that is difficult is predicting the mind of a Ghanaian voter," Akwetey said.

If Akufo-Addo wins, it will be the first time in Ghana since 1992 a head of state has to deal with an opposition-dominated parliament.

Chris Fomunyoh of the Washington-based National Democratic Institute said given the closeness of the vote, Ghana stands to gain from a second round of voting.

"An election this close shows a country politically split almost down the middle," he said after the first round.

"A second round will produce a clear cut winner with a mandate to govern and legitimacy that will not be contested for the next four years," he said.

If the second round goes off smoothly, Ghana could provide the shining example Africa needs after the crises that followed elections in Zimbabwe and Kenya this year, analysts said.