Well, I'm not sure how allowing Wade is reasonable.
That's the guy himself who limited the to 2 times 5 years mandates, and who even said 'I won't represent myself', but then it seems he wanted to create a golden armchair for his son and create a dynasty, and thus had tried preceding amazing constitutional changes in this sense last year, which created the street opposition movements against him, he withdrew them and now hides behind 'the mandate in which I was when I changed the Constitution [which did last 7 years] can't count'. I guess he's trying to get reelected to say 'now I've been chosen by the people, I can change the Constitution the way I want!', to create this golden path for the son.
About the fairness of results, according to a French journalist which has a good knowledge of Africa, Antoine Glaser, apparently the democratic tradition effectively became quite good in Sénégal, and for example, Karim Wade (the golden son) took a slap when he tried to get Dakar's Town Hall in 2009. That being said, yesterday during a debate on France24 with one representing Wade's party, and one other representing the Parti Socialiste Sénégalais, that latter spoke about a massive fraud of electoral cards recently discovered, but well, you can never know what is accurate in such debates.
There is also the fact that apparently still 300k to 400k electoral cards have yet to be distributed and the fat that last week the Céna, the independent electoral commission hadn't even received its budget to send the 18k observers all over the country.
That being said, on an other hand, there would be this well working democratic tradition so far, and several mission from abroad, notably a AU one and a EU one (euh, respectively 40 and 90 people though), which have been very well accepted by a spokesman of Wade.
Apparently if Wade isn't elected on the 1st round, and he arrogantly spouts 'I gonna be elected by 55%, others are not worth it', which doesn't help, it could be hard for him on 2nd round if the opposition succeeds to unite, which isn't guaranteed so far apparently.
If results show him losing, one can only hope he doesn't continue his arrogant attitude till Gbagbo level trying to stay on power using twisted results from the Constitutional Council of which the wage of judges would have been significantly increased if one believes the guy representing the PSS, because the street movements, which are not only in Dakar, might not easily accept it, and if results show him winning, one can also wonder how easily those same movements will accept it.
And well, one can also wonder how it will happen till the scrutiny day, because if apparently the Sufi brotherhoods try to stay rather out of it, the tear gas in a Tidiane/Tijane (different spellings), which led to a retaliating burning of the town hall of Tivaouane, which is the center of the Tidiane community, apparently led by pro-Wade mayor, could significantly contribute to radicalize people against Wade, and even to give more popular supports to those young movements if you believe some analysts from Sénégal, outside of the fact that it could eventually contribute to tensions between the 2 main religious communities of the country, Tidiane and Mouride.
Not much of an easy situation for some fair elections.