Philadelphia, Shawwal 21, 1437, Jul 26, 2016, SPA -- Delegates at the Democratic National Convention on Tuesday will hear from the man who probably knows Hillary Clinton best - her husband and former US president, Bill Clinton, AP reported. The convention's second day also will include a roll call of states in which delegate votes will be tallied. It is expected to deliver the historic moment when Clinton reaches the number 2,838, which will put her over the top and make her the first female presidential nominee of a major US political party. But the moment won't belong entirely to Hillary Clinton. Supporters of Bernie Sanders, who put up a strong challenge to the former secretary of state during the state-by-state primaries and caucuses, have vowed to make their voices heard on the convention floor. The disgruntled Sanders supporters look forward to an opportunity to show their dissatisfaction with the expected nomination of Clinton. There will be time for both Clinton and Sanders supporters to speak from the floor, but it will be largely a symbolic gesture for the Sanders camp. Sanders called for unity on Monday and said he stands with Clinton, but he also noted that 1,846 of the 4,700 delegates were pledged to him. Bill Clinton, who could become the first first gentleman to occupy the White House, has spoken at every Democratic Party convention since 1988, but this will be the first time a former US president has spoken in favour of his spouse following in his footsteps. -- SPA 21:30 LOCAL TIME 18:30 GMT www.spa.gov.sa/w