The firm had resurrected the historic brand in response to the decision by German rivals BMW to take control of the Rolls Royce marque, and Volkswagen's acquisition of Bentley.
Aston is rumoured to be in talks with Daimler to take over design and production of the German firm's Maybach luxury cars, rivals to Rolls and Bentley in price, if not in style and sales.
While Wowereit talked from the stage, his shirt unbuttoned and his jacket open, people lined up at the sausage booth, where three SPD members sold the charred wurst stuffed into rolls for 1.50 euro each (at least one German complained that they were too charred).