"We are going to fight to the end because every vote counts," she told a crowd of around 1,000 people waving orange "Angie" placards and chanting "Angie, Angie."
"We are the only party in Germany to govern the economy sensibly," she said. "Voters will decide tomorrow how quickly we get out of this crisis. We are fighting for the German jobs of the future."
Merkel, 55, has won plaudits at home and abroad for steady leadership through the crisis that has hit Europe's top economy harder than most, and surveys indicate Germans are in no mood for change at the top.
"This pastor's daughter from the east has governed with such self-confidence in the past four years that many of the 62.2 million voters will choose her even though they do not like her party. They want Merkel," commented the daily Süddeutsche Zeitung.
But her conservative party's lead over the centre-left Social Democrats (SPD) has shrunk and tension is rising as her hopes of governing with her preferred partners, the pro-business Free Democrats (FDP), hang by a thread.
If Merkel's Christian Democratic Union (CDU) and the FDP do not clinch a majority, the most likely outcome is another awkward "grand coalition" between the CDU and the SPD that has governed Germany since the inconclusive 2005 election. But Merkel insisted: "We can only have stability with a coalition between a strong Union and the FDP."
Supporters were impressed with her final performance.
"She did well. Certainly better than at the TV debate," said Katrin Sattelkau, referring to a televised "duel" between the two candidates two weeks ago which was broadly seen as lacklustre and dry.
"We are confident because there is no other direction possible for this
country," added Sattelkau, a 34-year-old doctor.
The SPD candidate, Foreign Minister Frank-Walter Steinmeier, was judged by many to be a weak campaigner at first. But he has steadily gained confidence and issued a rousing call to some 10,000 supporters late Friday at Berlin's Brandenburg Gate.
"The Union is getting more nervous by the day," Steinmeier told his flag-waving audience.
"The big lead they had has melted like ice in the sunshine. We will keep fighting for every vote until the last second on Sunday at 6:00 pm," he said, referring to when polling stations close.
Voters said the often reserved Steinmeier, a veteran bureaucrat who has never run for political office, had in the final weeks of the campaign developed the killer instincts needed in a candidate.
"I've never seen him better," said Monika Buttgereit, a 59-year-old teacher. "He was relaxed but feisty and he got across the main point - we have to stop Black-Yellow," she said, referring to the party colours of the CDU and FDP.
But the final campaign rallies took place amid heightened security throughout the country following a series of messages from Islamic militants warning Germany over its continued presence in war-torn Afghanistan.
The unpopular military deployment is just one of a host of problems the winner of Sunday's election with have to face, along with a record mountain of debt and Germany's worst economic slump for more than 60 years.
"Whoever receives from the voters the task of governing will need a great deal of strength, courage and optimism to overcome the challenges that lie before him, or her," Hannover's Neue Presse daily said in an editorial on Saturday.