Austrian President Alexander Van der Bellen secured a second six-year term in office on Sunday by winning a clear majority of votes in an election to avoid a runoff, according to projections based on almost all votes cast except postal ballots.

The 78-year-old former leader of the Greens has garnered broad popularity by projecting calm during times of national crisis, including the collapse of the government in 2019 and the resignation of Chancellor Sebastian Kurz a year ago over corruption allegations that Kurz denies.

The far-right Freedom Party (FPO) was the only party in parliament to field a candidate against Van der Bellen, who won a much tighter race against an FPO opponent in 2016. Grandees from all other parties in parliament backed the president.

The Austrian president performs a largely ceremonial role, but also has sweeping powers that mean overseeing periods of transition and turbulence. The president is the commander in chief of the army and can sack the whole government or the chancellor.

"A majority is easily said, but an absolute majority means more votes than all others (candidates) combined, and one must take that very seriously. I was not at all sure that it would happen but it did, and I am very pleased," Van der Bellen told national broadcaster ORF. He faced an all-male field of six opponents.

With 95 percent of the votes cast in polling stations counted, a projection by pollster SORA for ORF put Van der Bellen at 56.1 percent with a margin of error of 1.1 percentage points. His nearest rival was the FPO's Walter Rosenkranz at 17.9 percent.

"Alexander Van der Bellen really managed to ensure in the first round that he will be the next president. I congratulate him on that," Rosenkranz told ORF.

The votes counted on Sunday do not include postal ballots, which will be counted on Monday, but projections are for the result as a whole, including postal ballots. Those projections have proved highly reliable in the past.

A separate projection by ARGE Wahlen for news agency APA produced nearly identical results to SORA's, putting Van der Bellen at 56 percent and Rosenkranz at 17.6 percent, based on a count of 88 percent of votes cast in polling stations.