Dakar:  Togo's presidential vote is the latest in a string of disputed elections in Africa which risk undermining the trend of the last decade for political power to come through the ballot box.

Provisional results showing incumbent President Faure Gnassingbe the comfortable winner of last Thursday's poll were immediately challenged by his main rival, while police used tear gas to quell protests in the capital Lome over the weekend.  While the unrest is not seen matching that of the last poll in 2005, when hundreds were killed in a security crackdown on protests, the row highlighted just how difficult many African countries still find it to stage a credible election.

"The principle that you have to seek legitimacy through the ballot box is more entrenched then it was a decade ago," said Omaru B. Sisay of Exclusive Analysis.  "But the real danger with (disputed elections) is they might drive people who would otherwise seek power through a poll into the bush to try an insurgency," he said.

With the 2010/11 election calendar due to include tense votes in Guinea, Ivory Coast, Niger, Central African Republic, Liberia, Zimbabwe and Democratic Republic of Congo, the potential for further trouble is high.  Africa does not have a monopoly on election disputes, as shown by rows over polls last year in Iran and Afghanistan and the likelihood that the outcome of Iraq's parliamentary vote on Sunday will be contested.

However events around Togo's vote on Thursday bore all the hallmarks of what is emerging as a typically African experience of elections that have left nagging questions over the outcome, such as recent polls in Gabon, Congo Republic and Equatorial Guinea.  As in Gabon last year, the ruling Togolese party had the resources to ensure blanket billboard and campaign coverage of its candidate, ensuring that Gnassingbe was more visible than any rival from a fragmented opposition.

Even before official results giving Gnassingbe just over 60 percent of the vote were released on Saturday, rival Jean-Pierre Fabre hailed himself the winner, prompting a counter-claim from Gnassingbe on the government website.

With African and European observers raising concerns about procedural flaws but not questioning the result outright, Togo is now left in an uneasy limbo as it awaits the constitutional court ruling later this week needed to validate the result.

Sisay and others believe Gnassingbe, who deployed extra troops to secure the poll, is more able to contain protests than in 2005, when events exploded out of control and the subsequent crackdown killed up to 500, according to U.N. estimates.

Rolake Akinola of Global Risk Analysis said poll disputes in themselves did not automatically deter hardened investors in the region, who in many cases are able to live with leaderships of all hues as long as their assets are secure.  But she argued that they served to highlight how far many countries still have to go in consolidating the reforms which ensure a sense of confidence in elections, such as an independent judiciary and freedom of press and expression.

"For example, Nigerians have in general embraced democracy but elections there still remain turbulent," she said.

Increasingly sophisticated African electorates and tighter procedural checks are making it harder to rig elections in the blatant manner of the early post-colonial rulers who often claimed near unanimous backing from voters.

But Zimbabwean Prime Minister Morgan Tsvangirai's appeal on Sunday for international observers and peacekeepers to ensure a level playing field against President Robert Mugabe's camp next year demonstrates that fear of meddling remains alive.

Akinola said it was vital that foreign pressure is kept on coup leaders in Niger and Guinea to stage free elections for a civilian government this year. On Monday, Guinea said it would hold a presidential election on June 27.

The other big test being the long-delayed poll in regional giant Ivory Coast.

Sisay warned against failure to resolve a dispute over voter eligibility and other procedures holding up a election needed to reunite the country divided in two by a 2002-3 conflict.  "In Ivory Coast the stakes are so high," he said of the world's top cocoa grower and former regional economic engine. "There is a real risk of return to civil war."

*  Mark John filed this analysis for Reuters from Dakar