The second and decisive round of elections will be held on Sunday, after a first round in which eleven candidates ran.
The socialist Seguro, who is characterized as a center-left politician, is leading in opinion polls and is seen by many as a bulwark against a right-wing swing in Portugal.
The opposing candidate Ventura and his party, Chega, are considered far-right and have quickly become a strong force in Portuguese politics.
Around eleven million residents are eligible to vote in the elections. The president has limited powers, with a veto over parliamentary decisions and the ability to dissolve parliament.
