By Chris Mfula
LUSAKA (Reuters) - Zambia's ruling party candidate Edgar Lungu secured a narrow victory in this week's presidential poll, results showed on Saturday, defeating his closest rival who said the election had been "stolen".
The ballot was triggered by the death last October of the President Michael Sata. With another election scheduled for late next year when Sata's term had been due to end, Lungu will have little time to turn around a stuttering economy in one of Africa's most promising frontier markets.
Patriotic Front candidate Lungu won 48.3 percent of the vote to 46.7 percent for Hakainde Hichilema, a wealthy economist from the United Party for National Development, the Electoral Commission of Zambia said.
Hichilema accused the commission of manipulating the results in favour of Lungu -- a former lawyer with a laid-back, populist style.
"The stolen election does not reflect the will of the people of Zambia," he said. "If Edgar Lungu is sworn in, he should know that he is an illegitimate president."
Turnout for the election was around 32 percent as heavy rains disrupted voting across much of the country. Observers said the ballot was conducted in a fair manner.
Hichilema had hoped to draw his experience in the private sector to attract foreign investment and diversify an economy, where copper accounts for 70 percent of export earnings.
Zambia has averaged 6-7 percent growth as the mining sector boomed but that slowed to 5.5 percent last year, the International Monetary Fund said, and could ease further with the price of copper reaching a 6-year low this month.
Lungu used his campaign to tap the support of his predecessor Sata, promising voters cheaper food and fuel.
(Reporting by Chris Mfula; Writing by Tiisetso Motsoeneng; Editing by Robin Pomeroy)