The vote to choose a winner from the Swedish and Italian rivals is expected to be closer than the 2015 vote when Beijing beat the Kazakh city Almaty to land the 2022 Winter Games.
READ ALSO: Polls show Italians more enthusiastic about Winter Games bid than Swedes
On the road to the 2026 decision, bids from Calgary, Graz in Austria, Japan's Sapporo and Sion in Switzerland have fallen by the wayside, mainly because of concerns over the cost or a lack of popular support. A bid by the Turkish ski resort of Erzurum was ruled out by the IOC in October 2018.
The bid by Stockholm and the Are ski area -- which hosted the World Ski Championships in February -- appeared to be running out of steam a few months ago due to a lack of funding commitments, but the government has now swung behind it.
On the eve of the vote, Swedish Prime Minister Stefan Lofven said after meeting IOC president Thomas Bach: "Sweden is ready to host the Winter Olympic Games in 2026 and the Swedish government is very supportive."
Sweden presents its bid. Photo: Fabrice Coffrini/AFP
"While organising a great Games, we can end the age of extremely costly Olympics that threaten welfare spending and leave a trail of underused structures and public resentment," the Swedish prime minister said. "You wanted change; we will deliver this change."
Italian Prime Minister Giuseppe Conte followed the Swedes with his pitch for Milan on Monday.
"Our bid is worthy of the highest consideration," Conte told delegates. "If Italy is chosen, then work will start from this evening so that our Games leave a mark on history.
"This is the dream of an entire country, and not only the government but also the regions."
Italy's champion skier Sofia Goggia was in Lausanne to back the Italian bid. Photo: Fabrice Coffrini/AFP
Italian Olympic 500m short track speed skating champion Arianna Fontana highlighted the climate advantages of the bid. "Milan-Cortina will be the sunny part of the Winter Olympics, with an average ten hours of sunlight every day," she said.
Michela Moioli, Olympic snowboard champion in 2018, added: "The whole country believes in us; it's your turn to believe in us."
A total of 82 IOC members are reportedly likely to cast votes in the ballot to decide the host city, meaning a simple majority of 42 will be required to win.
Italy has twice hosted the Winter Olympics -- in 1956 in Cortina d'Ampezzo and 2006 in Turin. Sweden has only hosted the Summer Olympics, in 1912 in Stockholm.