Ramat Hasharon city councilmen Avi Gruber and Ya'acov Koretzki will face off in a run-off race for mayor in two weeks after none of the four candidates in Tuesday's mayoral election succeeded in winning the 40 percent of the vote needed to avoid a run-off. The special election is being held due to the conviction of former mayor Yitzhak Rochberger on corruption charges. Acting mayor Shira Abin, who ran the city for the last two years, finished third, ahead of city councilwoman Dovrat Weiser. Abin attacked Koretzki throughout the race, because he is a newly religious, black kippa clad candidate of the haredi (ultra-Orthodox) Degel Hatorah party. Gruber won the most votes in the first round and is favored to win the second.