Chancellor Gerhard Schroeder and conservative challenger Angela Merkel have held their final rallies in the German election campaign.
Both leaders go head-to-head in Sunday's elections
Mr Schroeder told rallies in Frankfurt and the industrial north-west that the welfare state was at stake.
His rival went to Bonn to urge a mandate for sweeping reforms to combat low growth and high unemployment.
With a quarter of voters said to be undecided, the parties will still be campaigning on polling day itself.
"We're fighting until 1759 [1559 GMT] on Sunday," said Green leader Claudia Roth, referring to the minute before polls close.
Opinion polls suggest Mrs Merkel's Christian Democrats (CDU) remain the most popular party but may not win enough votes with their preferred partners to form a governing coalition.
The choice on offer to voters is between the hand of the state managing a collective response to global competition and bolder free market reforms to shake up old habits, the BBC's William Horsley reports from Berlin.
A close result is expected in a contest that has raised strong passions in Germany and keen interest abroad.
Bonn, a CDU stronghold, saw a rally of 7,000 people cheering on Mrs Merkel.
"Vote for change because Germany needs a future," she told the crowd.
Aware of predictions that she and her Free Democrat (FDP) allies might not obtain an overall majority, she said a grand coalition was the last thing Germany needed.
She warned that Mr Schroeder's Social Democrats (SPD) might still join forces with parties further on the left to retain power.
Mr Schroeder cracked jokes at his rallies, telling an audience of 10,000 in Recklinghausen, in the Ruhr Valley, to round up anybody they could find.
"Think about bringing grandma and grandpa with you," he yelled in a hoarse voice, "but only if they're going to vote for the SPD."
In Frankfurt-on-Main, he told an audience of 18,000 it was "about every vote - even mine".
The CDU leader also visited the city, appearing at the international car show.
Opinion polls have consistently put the CDU in the lead but the SPD have been closing the gap.
It seems clear that the Christian Democrats will be the strongest single party but if they do not get enough votes to rule with the Free Democrats, they may be forced into an unpalatable coalition with the SPD.
The election will bring either a clear mandate for change under Mrs Merkel and her allies or the prospect of political stalemate, our correspondent says.
She has promised to go further than the SPD in cutting taxes and business regulation, and making welfare reforms.
The SPD says Mrs Merkel's policies would lead to rampant capitalism and poor social provision.
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