Nigeria relatively little violence or voter fraud, in contrast to previous elections. In the March 2015 election, Muhammadu Buhari defeated Goodluck Jonathan by roughly 2 million votes. Observers generally praised the election as being fair. Jonathan was generally praised for conceding defeat and limiting the risk of unrest. Nigeria is a federal republic modelled after the United States, with executive power exercised by the President. It is influenced by the Westminster System model in the composition and management of the upper and lower houses of the bicameral legislature. The president presides as both head of state and head of the federal
Head of state It could be argued that the strengthening of the Prince's powers, vis-a-vis the Landtag (legislature), has moved Liechtenstein into the semi-presidential category. Similarly the original powers given to the Greek President under the 1974 Hellenic Republic constitution moved Greece closer to the French semi-presidential model. Another complication exists with South Africa, in which the President is in fact elected by the National Assembly (legislature) and is thus similar, in principle, to a head of government in a parliamentary system but is also, in addition, recognized as the head of state. The offices of President of Nauru and President of Botswana