Campaigning for Sunday's presidential election in Senegal has begun to close with tensions raised by clashes between supporters of incumbent leader Abdoulaye Wade and those of one of his main challengers. The wooing of voters officially ends at midnight on Friday, sealing three weeks of a generally peaceful campaign marred by the violence on Wednesday night, which left about 10 people hurt in a nation presented as a model of democracy in Africa.The skirmishes pitting Wade loyalists against fans of former prime minister Idriss Seck caused concern after an otherwise calm pre-electoral period marked by street carnivals and musical jamborees as well as slogans and speeches. A spokesperson for the West African Civil Society Forum, which has deployed nearly 100 observers, on Friday described the run-up to the poll as "peaceful, even if people are apprehensive". A record 15 candidates jostling for the country's top job are likely to split the vote, which means there will be a second round if none of them garners the minimum 50% of ballots needed for an outright victory.