"President Adalberto!" chanted the crowd, dressed in the party colours of the National Union for the Total Independence of Angola (UNITA), as its leader Adalberto Costa Junior arrived.
The thousands of supporters -- mainly young people -- were feverish with excitement, chanting "the black rooster" in reference to UNITA's symbol.
"You're showing that Angola has a fighting spirit," Costa Junior told the crowds in response.
UNITA, a rebel movement turned political party, is one of seven opposition parties standing in Wednesday's elections.
But it is the main rival to the People's Movement for the Liberation of Angola (MPLA), which has ruled the oil-rich country since independence from Portugal in 1975.
"Don't be afraid of an alternative, long live free and fair elections. There is no democracy without changing of power," Costa Junior told supporters, who had gathered in a dusty field in the city's Cazenga neighborhood.
"There is no democracy with a single party in power."
The 60-year-old Costa Junior said youth represent a significant and growing voting bloc.
"UNITA's mandate represents the realization of a dream, the realization of the youths' goals," he said.
Supporters are enthused by Costa Junior's approach to politics, in building a coalition with other opposition parties to take on the MPLA.
"We are here because people want an alternative. Angola is a rich country but its people are suffering. It's very sad. We absolutely want an alternative," said Luis Santana, a street vendor who earns $5 per day.
UNITA has formed an electoral coalition with two other opposition groups to boost its chances of defeating the MPLA.
And the opposition's united front was clear to see on the rally podium.
Costa Junior was joined by the popular Abel Chivukuvuku, president of the PRA-JA Servir Angola party, along with the head of Democratic Bloc party, Filomeno Vieira Lopes.
An Afrobarometer survey in May showed support for the opposition was growing but still trailed by seven percentage points behind the MPLA.
The MPLA's final campaign rally was on Saturday but incumbent President Joao Lourenco held a special women's rally earlier Monday.
His running mate, Esperanca Maria Eduardo Francisco da Costa, would be the country's first female vice-president if the MPLA wins.
Despite the excitement over the opposition and high levels of despair and frustration among its mainly youthful supporters, analysts say that the MPLA however is likely to win the vote.