There was a 54-per-cent vote in the last election in 1990 but the turn- out in subsequent by-elections has been as low as 6 per cent.
Mr Mugabe's ruling Zanu-PF and five opposition groups headed by the Forum Party, under a former chief justice, Enoch Dumbutshena, are contesting 65 remaining seats in the 150-seat parliament.
Thirty independents, mostly Zanu-PF rebels, are also running in the poll.
Zanu-PF has already won 55 seats for lack of opposition candidates. Mr Mugabe fills 20 more seats with presidential appointees, while the remaining 10 go to traditional chiefs .
Yesterday the President emphasised his party's record of unity and reconciliation in a country racked by a guerrilla war against white minority rule up to independence in 1980, when Mr Mugabe took power.
One theme of the campaign has been attacks by government leaders on white "racists".
Asked yesterday whether he regarded "white racism" - to which he had referred in his speech - as a serious problem, Mr Mugabe said: "There are groups that stick to the past."
But he said these represented only "vestiges of the past", which could also be found in the United States.
There has been little policy discussion during the campaign. Mr Mugabe acknowledged that unemployment, around 50 per cent of those of working age, was a primary concern. It had been exacerbated by an economic-reform programme aimed at freeing the economy from government control.