Aides to the leader of the New Patriotic Party said he decided to stick to his prior campaign commitments, even though it meant missing the chance to present his message at one of the most high-profile events of the campaign.
Analysts say Akufo-Addo has a real chance of defeating Mahama or of taking the Dec. 7 election to a second round, largely because of voter discontent over an economic slowdown since the president won the first of two possible terms in 2012.
In the absence of a large number of reliable opinion polls, politicians on all sides say they expect a tight contest.
Ghana exports gold, oil and cocoa but has suffered from a slump in global commodity prices and macro-economic instability in the form of inflation that stood at 15.8 percent last month, an elevated budget deficit and high unemployment.
The government says the economy will recover after it increased revenues and took tough measures to limit public sector wages and spending. Some of the measures were taken as part of an aid programme with the International Monetary Fund.