These are potencial candidats (wikipedia source )
Who of them is the best option for you? Africa
The Freedom and Justice Party said that they would submit a proposal to host the 2028 Olympic Games in Egypt, most likely in Cairo, as an aim to boost the tourism sector and attract 25 million tourists per year. In preparation, Cairo's metro and airports are being expanded; in addition, a number of swimming venues been built across Egypt's governorates.
During the 2008 Summer Olympics, Kenyan Vice President Kalonzo Musyoka announced Kenya is considering a bid for the 2028 Games. It would dovetail with "Vision 2030", when Kenya expects to have the status of a developed nation.
In March 2011, the Moroccan Government confirmed that they would begin construction of an 80,000-seat capacity stadium in preparation for a bid for either the 2024 or 2028 Summer Olympics.
Durban, South Africa
Durban was the most likely South African candidate for the 2020 Summer Olympics, before the country withdrew its bid. If Durban does not win a 2024 bid, there is a possibility that they will bid for the 2028 Summer Olympics Europe
After failing to win their bid for the 2012 Summer Olympics, the city is now planning on bidding for 2028. The city previously hosted the 1980 Summer Olympics, when the USSR was still existent. North America
Los Angeles Los Angeles hosted the 1932 and 1984 Summer Olympics. Los Angeles bid to become the US applicant city for the 2016 Summer Olympics, though the USOC selected Chicago instead. In September 2011, Los Angeles was awarded the 2015 Special Olympics World Summer Games. In November 2011, a delegation from Los Angeles attended a seminar at the IOCheadquarters in Lausanne for cities interested in bidding on future Olympic Games. In February 2012, Los Angeles hosted the 5th IOC World Conference on Women and Sport. At the conference, Los Angeles Mayor Antonio Villaraigosa and IOC MemberAnita DeFrantz stated that that the city would be interested in hosting for a third time.
Philadelphia Larry Needle, executive director of the Philadelphia Sports Congress, hinted that Philadelphia is interested in bidding for a future Summer Games. Given that a U.S. host city for the 2024 Summer Olympics would have to be selected by 2015 and there are no current plans for a bid by the city and USOC, the 2028 Summer Games are likely the earliest opportunity for a Philadelphia bid. Philadelphia mounted a serious effort in 2006 to land the 2016 games and was one of five finalist U.S. cities. The feedback, says Needle, was that "Philadelphia is very viable as an Olympic city based on its facilities, infrastructure and the compact footprint for such a major city." However, Philadelphia was unfamiliar to the International Olympic Committee (IOC). A negative perception by the IOC was not a factor; instead, says Needle, "it was an unknown in those circles of people making decisions about major sporting events." Since 2008, Philadelphia has hosted several U.S. Olympic trial events as well as the International Fencing Federation meeting in 2011, which included several IOC delegates. Philadelphia bid for the 1920, 1948, 1952 and 1956 Summer Olympics, losing to Antwerp, London, Helsinki and Melbourne respectively. Oceania
Brisbane In August 2008, former Queensland Premier Anna Bligh stated that she believed that an Olympics bid in the 15 to 20 year time frame would be likely. Former Brisbane Lord Mayor and incumbent Premier Campbell Newman also stated that infrastructure to support an Olympic Games could be in place for a bid within 15 to 20 years. On 18 January 2009, the Australian Olympic Committee announced that Brisbane would make no bids for the 2024 Olympic Games. Brisbane's neighboring Gold Coast will host the 2018 Commonwealth Games. Brisbane previously bidded for the 1992 Summer Olympics, but lost to Barcelona.
Melbourne Melbourne is considering a bid for either the 2024 or 2028 Summer Olympics. The only major venue that would need to be constructed would be a rowing and canoeing course. The city hosted the 1956 Summer Olympics and the 2006 Commonwealth Games. The MCG served as the main stadium of both events, placing Melbourne in the situation of already having a high capacity main arena ready for any future Olympics. South America
Buenos Aires, Argentina
Buenos Aires is currently bidding to host the 2018 Summer Youth Olympics. If that bid is successful, it could lead for a bid for the 2028 or 2032 Summer Olympic Games. The city is also hosting the 125th IOC Session in 2013. Rio de Janeiro will stage the first Summer Olympic Game in South America in 2016. Buenos Aires could potentially be the second city on the continent to stage the event. Buenos Aires bid to host the 1936, 1956, 1968, and 2004 Summer Olympics, but lost to Berlin, Melbourne, Mexico City andAthens respectively. In my opinion, from Africa only Durban has chances to be shortlisted and eventaully to win.
Moscow would be 90% shortlisted, but because games will be in Sochi next year, not that big chances to win but who knows.
Any USA city can be shortlisted, and good chances to win if USA doesn't get games in 2024.
Australia, too early after Sydney.
Buenos Aires would be nice, but South America will wait couple years more, i think.