Cape Verde President Pedro Pires has narrowly won Sunday's election, according to official results.
Pedro Pires' party also won January's parliamentary poll
He received 51% of the vote, against 49% for his rival Carlos Veiga. In 2001, Mr Pires defeated Mr Veiga by just 12 votes.
With a small margin of victory again, the votes of the Cape Verde diaspora ensured victory for Mr Pires, the AFP news agency reports.
Mr Veiga has said he may contest the validity of the diaspora vote.
Mr Pires gained 2,856 more votes than his rival, according to the results, which have still to be confirmed.
AFP says 65% of Cape Verdeans living abroad backed Mr Pires, who led the struggle for independence from Portugal in the 1970s.
Economic development and the reduction of poverty dominated the election campaign.
Carlos Veiga lost by 12 votes in the last presidential election
Cape Verde has high unemployment, but is also seen as politically stable with an emerging prosperity.
Mr Pires' ruling African Party for the Independence of Cape Verde (PAICV) won January's parliamentary elections with 52% of the vote.
The two leading candidates have dominated politics in the tiny West African archipelago since it won independence from Portugal in 1975.
The PAICV first came to power under a one-party system after independence, with Mr Pires as Cape Verde's first prime minister.
Mr Veiga's Movement for Democracy (MpD) won the first multi-party elections in 1990.
The 56-year-old Mr Veiga served as premier for the next 10 years until the PAICV regained power in 2001.
About 325,000 Cape Verde citizens were registered to vote. Of these, about 20% live abroad - mostly in Portugal.