BERLIN, Dec 15 (Reuters) - Werder Bremen thumped Bayer Leverkusen 5-2 on Saturday to move level on points with tiring leaders Bayern Munich at the halfway stage of the season. Bayern did just enough to hold on to top spot, and claim the honorary title of 'winter champions', with a goalless draw away to Hertha Berlin. They now lead Werder only by goal difference, though, after Thomas Schaaf's side recovered from their Champions League exit in midweek by clinching a great comeback win. The highlights for the crowd were two goals from Ivan Klasnic, the Croatian striker who recently returned after two kidney transplant operations this year. The results put both Bayern and Werder on 36 points from 17 matches, four ahead of third-placed Hamburg SV, after they needed a last-gasp equaliser from Ivica Olic to grab a 1-1 draw away to Karlsruhe. Leverkusen stay fourth on 30 points, with Schalke 04 up to fifth a point further back after they won 2-1 at home to Nuremberg. After Sunday's remaining two matches, the Bundesliga takes a break until Feb. 1, by which time Bayern will hope to have recovered their sharpness. BAYERN HELD This was their second successive goalless draw and once again they looked short of ideas. Luca Toni was missing through injury but Ottmar Hitzfeld could still call on Germany strikers Lukas Podolski and Miroslav Klose and French playmaker Franck Ribery and the coach will be concerned at how poorly his side looked going forward. Werder had no such problems up front, although they did take a while to get going. Bayer Leverkusen had arrived at the Weserstadion on a five-match winning run in the Bundesliga and they looked likely to extend their record as Tranquillo Barnetta gave them the lead in the sixth minute. Klasnic, making only his third appearance since recovering from his two operations, struck the equaliser after half an hour and Diego put Werder ahead at the start of the second half. That opened the floodgates and the home side surged 5-1 clear before Stefan Kiessling got a consolation 14 minutes from time.