It's D-day in the Labor Party leadership race on Tuesday and D stands for delivery. Representatives of the five candidates will visit the party's Tel Aviv headquarters to deliver thousands of membership forms ahead of Tuesday's 4 p.m. deadline for members who join Labor to be eligible to vote in the May 28 primary. In the 2005 race, candidates brought crates full of membership forms, thousands of which were later disqualified by an internal investigation led by a retired judge. The rules were since changed to require a separate personal check for each new member, but the results of the drive were expected to be no different, with each candidate claiming an exaggerated number of new members to their credit. Before the drive, Labor had fallen to an all-time low of 57,000 members. The number had already risen by Monday to nearly 80,000 and it is expected to rise significantly Tuesday. Labor chairman Amir Peretz, who registered some 50,000 members in 2005 will apparently suffice this time with some 20,000, many of whom are Israeli Arabs who joined to thank Peretz for the ministerial appointment of MK Ghaleb Majadle. MK Ami Ayalon is claiming 25,000 members, many of whom are young people from Tel Aviv who had never joined a party before. "He will take the other candidates to school," Ayalon's spokeswoman promised. MK Ophir Paz-Pines intends to visit Labor headquarters on Tuesday morning with several thousand forms. Representatives of MK Danny Yatom will also bring a few thousand. Only former prime minister Ehud Barak refused to say how many members joined to support him. Barak's associates said he intended to draft support from the members brought by other candidates. Barak, who returns from a business trip to the US on Tuesday, received an endorsement on Monday from former Labor chairman Amram Mitzna. Mitzna was once a close friend of Barak but later became a fierce critic. He said Monday that Barak was the best candidate to be Israel's next defense minister. Yatom vowed on Monday to not endorse Barak and to stay in the race until the end. Tuesday is the deadline for candidates to join the race. The Labor faction decided on Monday to oppose the so-called Peres bill that would end secret ballot voting for the president. Peretz told the faction that the party must stick to its principles and prevent Prime Minister Ehud Olmert from changing the rules to elect Vice Prime Minister Shimon Peres. Foreign Minister Tzipi Livni defended her support for the bill on Monday, saying that it was not a personal bill, because it need not influence how MKs vote. She said she would support an amendment to the bill proposed by Kadima MK Marina Solodkin preventing factions from imposing faction discipline in the vote for president. Solodkin supports the candidacy of Labor MK Colette Avital. MK Ghaleb Majadle (Labor) officially became the first Arab minister Monday when the Knesset approved his minister without portfolio assignment. Fifty-nine MKs voted in favor of the appointment, while 23 opposed it, and two abstained. Majadle's friends and family were present in the plenum during the vote. Sheera Claire Frenkel contributed to this report.