BONN Chancellor Helmut Kohl went on the offensive in his battle for reelection on Saturday, vowing to score a come-from-behind victory against rival Gerhard Schroeder in Germany's September general election. Kohl, pictured shaking his fist by best-selling newspaper Bild, warned that if Social Democrat Schroeder broke his 16-year grip on power Germany would become a second rate country. The match is only over when the referee blows the final whistle, Kohl told Bild in an interview.