Labor MK Shelly Yacimovich made a surprise announcement of support for former prime minister Ehud Barak on Sunday night ahead of Tuesday's Labor leadership runoff race. Yacimovich, whose emphasis on socioeconomic issues is valued by Labor members, said that neither candidate had ideal views on economic issues, but she believed Barak would have a better chance of beating former prime minister Binyamin Netanyahu than Ami Ayalon. However, nearly three out of every four Israelis believe that Barak is not fit to reassume that post, according to a Smith Research poll first published on Yediot Aharonot's Web site on Sunday. When asked who was fit to be prime minister, 73 percent of respondents said Barak was unfit and only 25% said he was fit. The poll found that 34% of respondents found Barak's competition in Tuesday's Labor race, MK Ami Ayalon, to be prime ministerial material and 43% considered him unfit. By contrast, Likud leader Binyamin Netanyahu received a positive ratio, with 54% saying he was fit to be prime minister and 44% deeming him unfit. The poll also found that Ayalon brought Labor seven more mandates than Barak, 23 to 16. "The poll proves that Ayalon is the only candidate who can beat Netanyahu and return Labor to power," the Ayalon campaign said. "After he wins the Labor race, he will unite Labor, restore the public's trust in the party and return it to power." Barak's campaign responded that similar polls existed before the first round of voting two weeks ago and yet he still finished first. In an interview with Army Radio on Sunday, Ayalon vowed that he would not sit in a government led by Prime Minister Ehud Olmert, whom he accused of "eroding the concept of responsibility to the public and losing the public's trust." Asked about his repeated changes of opinion on whether Labor should remain in Olmert's government, he said it was better for a leader to adapt to different circumstances than to remain silent all the time - a reference to Barak's silence during the campaign. Barak campaigned on Sunday in Zichron Ya'acov. He was endorsed on Sunday by social activist Mauzya Segal and Simcha Banita, an activist for the disabled who is affiliated with Shas. Barak's spokesman said his main goal in the last couple of days of campaigning would be to reach out to Labor members who did not vote in the first round.