The president's main challenger is Michael Sata
Polls suggest Zambian President Levy Mwanawasa could face a strong challenge in Thursday's presidential and parliamentary elections.
Mr Mwanawasa's economic reforms and anti-corruption drive have won international praise, but many in Zambia accuse his government of doing too little to combat poverty.
The president's main challenger, Michael Sata, has made poverty his main campaign theme, and has threatened to deport foreign businessmen he accuses of exploiting Zambians.
Who is the incumbent?
Levy Mwanawasa won his first term as president in 2001, succeeding Frederick Chiluba.
He is one of the founding members of the governing Movement for Multiparty Democracy, which ended Kenneth Kaunda's 27-year rule in Zambia's first competitive election in 1991.
As president, Mr Mwanawasa has pursued a policy of economic liberalisation, coupled with a campaign against corruption.
The anti-corruption drive has even reached his predecessor, Mr Chiluba, who is charged with the theft of almost $500,000 during his term in office. He denies the allegations.
Mr Mwanawasa has also pledged to improve health, education and the country's infrastructure, as well as to modernise agriculture and tourism.
Who are the other contenders?
President Mwanawasa's main challenger appears to be Michael Sata, the leader of the small opposition Patriotic Front party.
Mr Sata has accused Chinese, Indian and Lebanese businessmen of exploiting Zambian workers and says he will expel them from the country if elected.
Mr Chiluba has thrown his weight behind Mr Sata.
Hakainde Hachilema, the candidate of the opposition United Democratic Alliance (UDA) coalition, says he will focus on practical measures to improve Zambians' lives.
The remaining two candidates have made little impact in opinion polls.
What are the main issues?
The economy is the main bone of contention.
President Mwanawasa says his government's policy of tight public spending and economic liberalisation has boosted growth and attracted foreign investment.
Growth in 2005 was 5.1%, and inflation has dropped from 30% to 8% since 2001.
In June 2005, international lenders agreed to write off a large chunk of Zambia's foreign debt as a reward for what they described as good economic management.
However, the opposition argues that too little of the benefits have trickled down to ordinary Zambians.
Almost 70% of Zambians still live on under $1 a day, while the average per capita income of $395 puts the country among the world's poorest.
What do the polls say?
An opinion poll published on 9 September had Michael Sata in the lead with 52% of the vote. Mr Mwanawasa was on 27%, with Hakainde Hachilema in third place on 20%.
Five days earlier, another poll gave the president a 33%-24% lead over Mr Sata.
How does the political system work?
Zambia is a presidential republic, in which the president is both head of state and head of government.
He or she is elected for a five-year term, with only a simple majority needed to win.
The parliament has 150 members elected in single-member constituencies. Another eight MPs are appointed by the president.
Which parties are standing for parliament?
Mr Mwanawasa's party, the Movement for Multiparty Democracy, is popular in the capital, Lusaka, and central Zambia.
At the last parliamentary election in 2001, it won 69 seats.
The United Democratic Alliance includes the main opposition United Party for National Development (UPND) and the former ruling United National Independence Party (UNIP) of Kenneth Kaunda. The UPND is strong in the south of Zambia.
In 2001, UPND won 49 seats, and UNIP 13.
Michael Sata's Patriotic Front, which won one seat in 2001, has formed an alliance with another small party and is strong in northern Zambia.
What happened at the last presidential election?
Mr Mwanawasa won with only 28% of the vote, only 2% ahead of his closest rival, Anderson Mazoka of UPND.
Opposition parties alleged widespread irregularities.
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