DAKAR - Senegalese President Abdoulaye Wade faces a tough presidential election run-off against his nearest rival after a campaign aide said on Tuesday that partial results ruled out a clear first-round victory.Wade’s bid for a third term at the age of 85 has prompted deadly street protests in the usually peaceful West African state, though voting on Sunday was calm and well-organised.Critics have said the constitution bans Wade, who has been in power for the last 12 years, from seeking a third term, a charge he has brushed off.With results from around half the country’s polling stations in, he was on 32 percent, ahead of former ally Macky Sall on around 25 percent but still well short of the 50 percent required for outright victory.With full results still unavailable, representatives from the European Union and the United States said they thought a first-round victory was increasingly improbable."The results that we have clearly indicate that there will be a second round. We don’t need to be told it,” Wade campaign spokesman Amadou Sall told Reuters by telephone. "We voted peacefully, with dignity and in complete transparency. We don’t need to be taught any lessons - we know how to count.”Senegal is the only nation in mainland West Africa that has not suffered a coup since independence - from France in 1960 - and the continuation of its stable democratic record is seen as crucial in setting an example for the coup-prone region.Attention is now likely to swiftly turn to a run-off.