President of Argentina
Under the 1994 constitutional amendment, the President serves for four years, with a possibility of immediate reelection for one more term. However, unlike the President of the United States, in Argentina, a person may be reelected again after serving for two terms and staying out of office for the following term. So after serving for two consecutive periods, the president is not allowed to run for a third consecutive one, but may return for the two following elections and so on. There is no limit for a person to be a candidate if he or she does not win the elections.
President
In Mexico, the president is "directly" elected for a six-year term by popular vote. The candidate who wins the most votes is elected president even without an absolute majority. The president may never get another term. The 2006 Mexican elections had a fierce competition, the electoral results showed a minimal difference between the two most voted candidates and such difference was just about the 0.58% of the total vote. The Federal Electoral Tribunal declared an elected president after a controversial post-electoral process.