Raila Odinga, leader of the opposition party Orange Democratic Movement (ODM), has opened his campaign to succeed Mwai Kibaki as the fourth president of Kenya when the country goes to the polls in December. Thousands of mostly male supporters wearing orange t-shirts flocked to Nairobis Uhuru Park on 6 October for the official launch, causing heavy congestion along roads leading into and out of the centre. There were also smaller isolated demonstrations involving chanting and dancing in nearby roads. The five-hour rally was broadcast live on television.

Odinga is the main challenger to president Kibaki, who is seeking a second term in office. Member of parliament for the Langata community in Nairobi, which includes the citys largest slum Kibera, Odinga is hoping to tap the disenchantment felt especially by poor Kenyans with the present government, which some say has not lived up to its 2002 election promises.

The other main candidate for president is Kalonzo Musyoka of ODM-Kenya, an opposition party which broke off from ODM earlier this year following a leadership dispute. He is due to launch his campaign on 13 October.

The launch of Odinga's campaign coincided with the announcement by the health minister, Charity Ngilu, that she would be supporting the ODM leader in the presidential race. She has now been sacked from the government.