By Ray Furlong
BBC correspondent in Berlin
Oskar Lafontaine has made a dramatic political comeback
Veteran east German pop group Die Puhdys are piped out across a small crowd of mostly grey-haired holidaymakers, gathered around the stands selling smoked fish near the beach.
The small resort of Glowe, on the Baltic island of Ruegen, is witness to one of the first rallies of the election campaign.
The sun is shining and the atmosphere is relaxed as Lothar Bisky, leader of the reformed communist party, the PDS, tells the crowd that "East Germany will have a voice again" after the election expected in September.
"We will re-enter parliament and the East will make itself heard again: what's going wrong here, and what our proposals are for putting it right," he says, to a ripple of applause.
Mr Bisky can afford to be confident.
His party recently made an agreement to form a new left-wing alliance with a motley grouping of disaffected trade unionists and former Social Democrats (SPD) in the west of Germany.
Simply called "Die Linke" (The Left), the new alliance has surged to 12% support in opinion polls - and blown the election wide open.
The secret of its success is another man: Oskar Lafontaine.
Once the leader of the SPD, he resigned as finance minister in 1999 and spent years in the wilderness - but has now returned to politics.
"Many people take this as a sign that there's a change in Germany, and the people hope that we combine the power of the Leftists, and people like this. They want it," says Mr Bisky.
"So we are going through a good time. We come together with Lafontaine and for the first time the leftists in east and west come together."
Mr Lafontaine has been bitterly criticised by the SPD for "populism".
In particular, after he complained about foreign workers coming in and taking Germans' jobs - using the term "Fremdarbeiter" (foreign worker) once used by the Nazis - instead of the more neutral "Gastarbeiter" (guest worker) generally used.
"I can't help it if the Nazis spoke German," was his blunt response to the criticism.
As the new alliance presented its election manifesto on Friday, he found another theme: Germany should pull its troops out of Afghanistan, he said, saying the international "war on terror" had led to attacks on the nations involved in it.
"We need to think about how to protect Germany from international terrorist attacks," he said, adding: "the Bundeswehr is deployed in Afghanistan in order to take part in the war on terror."
The CDU's Angela Merkel does not want a "grand coalition"
The party has also called for higher wages in Germany, to boost domestic demand, and pledged to make pensioners "once again proud to walk the streets."
So the new left-wing party has a very traditional socialist message.
But it seems to be a message the voters want to hear - and it is causing as much of a headache for the conservatives (CDU/CSU) as for Chancellor Gerhard Schroeder, because it is mobilising people who would not otherwise have voted.
"Until recently, we expected the CDU leader, Angela Merkel, to be the next chancellor in a government along with the liberals (FDP)," says Moritz Schuller of the Tagesspiegel daily.
"Now we will probably see a coalition between the Social Democrats without Schroeder - he will have to disappear - and with Merkel. She will still be chancellor, because she will win the election. But it will be a less impressive win."
A new coalition?
Mrs Merkel has so far ruled out the possibility of forming a so-called "grand coalition" with the SPD. The hope seems to be that the support for the new party is a bubble that will burst.
"I don't expect them to get twelve per cent. I'm confident that we will get a majority for the centre-right," says CDU deputy Christian Schmidt.
"A grand coalition would be one of the worst outcomes for our country - because there would be no possibility to change what has to be changed, to get a ticket for reform."
But whether this is true or not, opinion polls show that a grand coalition is the most favoured outcome among German voters - who believe it can help in times of crisis.
Whether it ultimately comes about depends to a great deal on how well or badly Die Linke fares on polling day.