BUENOS AIRES - Tokyo, Istanbul and Madrid were on Friday preparing to celebrate or commiserate their 2020 Olympics bids, as political leaders from all three countries make a final push to clinch the Games.

Members of the International Olympic Committee (IOC) vote on Saturday afternoon in Buenos Aires, with bookmakers putting Tokyo just in front of Madrid as favourites and the eagerly-awaited result to be beamed live across the world. Questions over safety have dogged Tokyo’s bid, however, because of the meltdown at the Fukushima nuclear plant after the devastating 2011 earthquake and tsunami while Madrid has faced fears about the state of Spain’s recession-hit economy.

Istanbul, meanwhile, has been in the spotlight after a heavy-handed crackdown on anti-government protesters earlier this year and the bloody conflict in Turkey’s neighbour Syria. Japanese Prime Minister Shinzo Abe, his Turkish counterpart Recep Tayip Erdogan and Spanish premier Mariano Rajoy were all due in the Argentine capital on Saturday in a last-ditch effort to persuade IOC members of their cases. In the bid cities themselves, though, final preparations were under way to mark the decision.

Tokyo’s super-efficient underground train system has for months been awash with posters showing the triumphant faces of Japanese athletes at the 2012 Games in London.

“Next time, this feeling could be felt in Japan,” the posters read, with an upbeat mood across the city reflected in increasingly glowing reports on the city’s chances. The education ministry last month said a survey suggested that a massive 92 percent of the public supported Japan hosting of large-scale sporting events.

“I am looking forward to hearing the decision tomorrow (Saturday),” said Ciro Cabal, a 28-year-old biologist, pausing as he did stretches after jogging in the Retiro. “To have a world event like this would be good for the economy, and to get back all the money they have invested.” Just down the road, Madrid city hall was hosting a small exhibition on the city’s plans for the Games, showing how its many existing venues such as Real Madrid’s Santiago Bernabeu stadium and the Las Ventas bullring would be used.

“I am from Madrid and I was born here. I have seen how it has evolved in all its aspects. I am proud of Madrid and especially of the transport network we have,” said Francisco Moreno, 78, visiting the exhibition with his grandson Diego, 10. A survey released on Thursday by market research group Opinea said 77 percent of Spaniards questioned were in favour of Madrid’s bid, while Spanish Formula One driver Fernando Alonso said Madrid “deserved” the Games after two previous failed bids.

In Istanbul, thousands of people are expected to watch the IOC vote on giant screens at Sultanahmet Square, between Hagia Sofya and the Blue Mosque. Sports minister Suat Kilic told the Hurriyet newspaper that Istanbul was ready both economically and in terms of support. “Everyone did their share for Istanbul 2020... We have reached out to all delegates who are going to vote... We have already deserved Istanbul 2020,” he wrote.

Optimism for a first Olympics in a predominantly Muslim country were high but in Istanbul, as elsewhere, not everyone was upbeat. “I didn’t know the decision was to be made tomorrow,” said Kemal Ozturk, a waiter. “Hosting the Games would be a great news for us, it would mean more business and more tourists. But I don’t think they are ready to grant the Games to Turkey because of what happened in Gezi Park last June.”

In Tokyo, a small group took to the streets last weekend to demonstrate against Tokyo’s bid, saying the huge sums of money required for the Games would be better spent on welfare. Protestors said they were also worried about the effect of the leaking Fukushima nuclear plant 220 kilometres (135 miles) north of the city.