The ruling Botswana Democratic Party won 38 of the 57 seats in the National Assembly on Friday, while the opposition coalition Umbrella for Democratic Change won 15.

The long peaceful, diamond-rich southern African nation had expected its tightest election in history after former President Ian Khama broke away and announced his support for the opposition coalition instead.

Khama hand-picked Masisi as his successor when he stepped down last year after two terms but was annoyed when Masisi moved away from some of his policies and began to crack down on corruption.

Many had wondered whether the ruling party would be toppled for the first time since independence in 1966.

But one political analyst said the ruling party benefited from sympathy votes especially in urban areas like the capital, Gaborone, where many people believed Khama wanted to perpetuate his hold on power.

"There was a feeling Masisi was not being given room to be his own man," Alvin Yalala said.

"There were also many people who would ordinarily vote opposition who supported Masisi to snub Khama, who is not popular among the middle class."

Another reason for the ruling party's win was that some voters saw the opposition coalition's alignment with Khama as a betrayal of principle, Yalala said.

"They wanted opposition as an alternative and not as an appendage of the former president."

Observers said Wednesday's election went smoothly in one of Africa's most stable countries. Turnout was not immediately clear. Botswana has 925,000 registered voters in a population of 2.2 million.

Australian Associated Press