If an election were to take place this summer, Labor would get 20 seats, according to a poll commissioned by the party.
Opposition leader Shelly Yechimovich cited the poll at Sunday's Labor Conference, saying that most of the increase in seats comes from "centrists," meaning former Kadima voters, but some come from Likud supporters disappointed by the current government's policies.
"We have unrealized potential, and we will not give up," Yechimovich said in her opening remarks, which were brief, as she is recovering from pneumonia.
Yechimovich's candidates to lead Labor institutions won all of the votes almost unanimously, including former justice minister David Libai, who will head the party's constitution committee.
The party leader's opponents, including MK Amir Peretz, stayed quiet throughout the conference, though someone shouted "This is like Syria!" after several motions passed with only a few Labor members opposed.
The conference also voted on a new policy requiring 40 percent of the representatives in any party institution to be female.
"Politics is full of challenges for women, and this step will increase political participation and create more equality for over 50% of the population," Yechimovich said.