Marcelo Rebelo de Sousa receives at least 60 percent of the vote, according to forecasts published in the country's largest media.
Thus, he seems to have a good margin to the 50 required to win already in the first round.
The popular 72-year-old - who was previously party leader for the liberal-conservative PSD - clearly had the greatest support in the opinion polls in advance.
The only obstacle on the way to five new years was judged to be an apostasy among voters.
Extensive restrictions have been in place in Portugal for the past ten days due to an increasing spread of infection.
If too many had stayed at home, it could have forced a second round.
The Social Democratic Socialist Party's candidate Ana Gomes comes second, as expected, followed by André Ventura from the right-wing populist party Chega (which means "Enough", as in "Now that's enough").
Most of Portugal's politics are controlled by the prime minister and the government, but the president has a mandate to nominate the prime minister and dissolve parliament - and is also commander-in-chief of the country's armed forces.