- Olympics news
D-Day for 2020 Olympic bidsESPN staff September 7, 2013 « Live County Championship coverage | Mayweather Jr is running scared of me - Alvarez »
The three cities vying for the 2020 Olympics are set to make their final pitches in a tight race that could be decided by just a few votes in Argentina.
Istanbul, Madrid and Tokyo will make 45-minute presentations on Saturday morning ahead of the vote later in the day by the International Olympic Committee (IOC).
Leading the delegations will be the prime ministers of the three countries. Shinzo Abe of Japan, Mariano Rajoy of Spain and Recep Tayyip Erdogan of Turkey all flew to Buenos Aires straight from the G-20 summit in St Petersburg, Russia.
Picking the city with the fewest risks shapes up as the challenge for the IOC.
Tokyo has been seen as a slight favourite, but its status has been put into question by concerns over the leak of radioactive water from the crippled Fukushima plant.
Madrid, once counted out because of Spain's financial troubles, has generated the most recent buzz and momentum, and could be poised for an upset win.
Istanbul, dogged by the war in neighboring Syria and possible Western military strikes against Bashar Assad's regime, looks like the outsider.
London bookmakers have been taking a rush of bets on Madrid, whose odds have been slashed from 4/1 a week ago to 5/4. Tokyo remains the favourite, although their odds have shortened to 5/6. Istanbul is listed at 6/1.
IOC elections are extremely unpredictable, as members vote by secret ballot and take different personal reasons into account. Some members are still undecided and will be waiting for the final 45-minute presentations before making up their minds.
If all IOC members are in attendance, 97 will be eligible to vote in the first round. With a majority required for victory, the process is likely to go to two rounds. The city with the fewest votes is eliminated after the first round, setting up a final head-to-head ballot. Outgoing IOC president Jacques Rogge will open a sealed envelope to announce the winner.
All three are repeat bidders: Istanbul for a fifth time overall, Madrid for the third straight occasion and Tokyo for the second in a row.
Previous bid campaigns have been marked by overriding geographic or emotional factors. In 2009, the IOC awarded the 2016 Olympics to Rio de Janeiro because of the Brazilian city's push to take the games to South America for the first time.
There has been no feel-good theme this time, as the campaign has been dominated by the negatives surrounding each bid: Syria, doping scandals and anti-government protests in Turkey; severe recession and 27% unemployment in Spain; and, most recently, the Fukushima leak in Japan.
Many members also will be voting with Rio in mind. The Brazilian city has been plagued by construction delays and other issues in their preparations for 2016, leaving members in search of a safe, reliable host for 2020.
Tokyo has championed itself as the "safe pair of hands" but has been on the defensive this week because of Fukushima. Some IOC members are looking for Abe to deal with the issue directly in Saturday's presentation.
On Friday, Tokyo organisers gave the clearest response so far on the leak.
Hiroshi Hase, a former Olympic wrestler and member of the Japanese parliament, minimised the problem with a detailed presentation - a strategy that had been lacking for several days as Japanese officials struggled with the subject.
"There is a very limited area where contaminated water is leaking out in the port. But we will monitor it, remove it and contain it. That is the gist of the strategy," Hase said.
Madrid has gained the most ground in recent months. The turnaround started at the bid city technical presentations in Lausanne, Switzerland, in July, when the Spaniards pressed their case that they offer the safest financial option: 80 per cent of the venues ready and only £1.2 billion needed for construction.
Madrid also has a star performer in Crown Prince Felipe, a former Olympic sailor and Spain's flag-bearer at the 1992 Barcelona Games. He wowed the members in his speech in July and will be Madrid's featured speaker in Saturday's presentation.
Istanbul is pitching its case as a "historic choice" for the IOC: the first Olympics in the region, the first in a city linking two continents, the first in a predominantly Muslim nation.
Download ESPN's new UK sport app, a fresh and powerful new way to follow your favourite UK sports news, scores and video.
Extracts from this piece originally appeared on ESPN.com