It's not impossible. Two years ago, If I'm not mistaken, the portuguese national title was disputed beetween two riders who escaped the peloton. Even though the circuit was a bit different it doesn't matter. Roads around Pataias are flat period.
Curiously... in that edition....João Cabreira won by beating Mário Costa (brother of Rui Costa).
IMO, Mauel Cardoso is the favourite. Portuguese teams will have to decide what's their best shot against him. Drag the peloton to the line and bet in the sprint or win it from a break.
Edit: must read all the posts, sorry Libertine