At stake is the opportunity to reach national conventions on 27 March in the capital, Abuja, where candidates for Nigeria's only legal parties, the National Republican Convention (NRC) and the Social Democratic Party (SDP), will be chosen to contest the 12 June presidential election.
Leading candidates for the SDP, whose strength lies in the mainly Christian south, are Moshood Abiola, a multi-millionaire Muslim businessman, the former party chairman Baba Gana Kingibe, and Atiku Abubakar, a disqualified gubernatorial candidate. The NRC frontrunners include Bashir Tofa, a banker, the former agriculture minister Sama'ila Mamman, and Dalhatu Sarki Tafida, formerly a personal physician to Shehu Shagari, whose government General Babangida helped to overthrow in 1983.
Today's attempt to choose candidates is the third in six months. The military government cancelled two previous sets of primaries, which were marred by widespread vote-rigging.
The campaign has failed to spark much enthusiasm among a public faced with soaring prices caused by massive government overspending and a steep decline in the value of the national currency, the naira.
One pound sterling cost 36.4 naira at the Central Bank yesterday and 44 on the street - and the naira's value has fallen from pounds 1 in the early 1980s. Over the same period the price of its key export, oil, has also declined, and the annual per capita income dropped from dollars 1,000 ( pounds 685) to dollars 290.
In the run-up to the primaries, the government has moved to silence critics. The Reporter newspaper of Kaduna, the political capital of northern Nigeria, was shut down and its editor detained on 1 March after it asked: 'Nigeria's prevailing mess: Babangida to blame?' The previous week, 100 armed police searched the Civil Liberties Organisation (CLO) headquarters, and confiscated documents.
A civilian Transitional Council, headed by a businessman, Chief Ernest Shonekan, has pledged to slash government spending and put the economy back on the road to structural adjustment. Western creditors have insisted on an agreement with the International Monetary Fund before considering major write-offs on Nigeria's dollars 27.5bn foreign debt. Debt payments account for one-third of the country's foreign exchange earnings.
Critics of military rule question the council's role. It was established in January after Gen Babangida changed the name of the Armed Forces Ruling Council to the National Defence and Security Council and postponed the army's return to barracks for the third time in three years. Real power, especially the power to spend, resides not in the civilian transitional council but in the NSDC.
A series of public sector strikes forced the government to cave into wage demands. A number of governors have warned that the pay rises threatened to bankrupt their states, and have accused the military authorities of deliberately straitjacketing state finances.