Zimbabwe's ruling party has won a crucial by-election, bringing it within two votes of a two-thirds majority in parliament, which would enable it to change the constitution easily. The victory came in a constituency in the southern Matabeleland Province, which has been one of the strongest areas to the opposition Movement for Democratic Change.

The Lupane constituency in western Zimbabwe has been a safe seat for the MDC since it fought its first election in 2000. That year, it won the seat in Lupane with five times more votes than the ruling Zanu-PF party.

Two years later in the disputed presidential election, its majority was smaller, but still two-to-one. There were allegations of fraud because there were 3,000 new voters in that election, although the population of the area is decreasing.

This time, a further 3,000 voters switched sides, according to the results of the weekend voting, published on Monday. Zanu-PF won the election by 800 votes, of about 20,000 cast.

This was the fifth by-election won by the ruling party since the 2000 general election.

All elections in Zimbabwe are run by the government, and no independent monitors are allowed, including the long-established Zimbabwe Election Support Network. The Network sent observers to the Lupane district for this election, but they were not allowed to examine any electoral materials.

An education officer with the Support Network, Emma Chiseya, was at the Lupane election, and said she and her team were surprised to see mostly older people voting. She said many young people have moved out of the area in the last few years.

Ms. Chiseya also said traditional leaders were taking down the names of people who voted in some parts of the district. The traditional leaders recently received a large increase in the stipends paid to them by the government. They refused to be interviewed by the team of observers.

The losing candidate, Njabuliso Mguni, a well-known teacher in the province, said he had to give up his job with the civil service in order to run in the election, because no one is allowed to remain on the government payroll if they run for election as an opposition candidate.