There will be at least five presidential hopefuls onstage for the first Democratic debate on Tuesday night and one conspicuous absence in Vice President Joe Biden -- although he will have a podium available onstage just in case, the Daily Mail reported.

Hillary Clinton, Sen. Bernie Sanders, former Maryland Gov. Martin O'Malley and former senators Jim Webb and Lincoln Chafee are slated to appear, but Biden is still mulling whether he will even run for president, the Daily Mail stated, adding that CNN, the debate host, has already rewritten its participation rules to allow the vice president to participate even if he doesn't declare his candidacy until start time.

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“The vice president should have made the decision a long time ago,” said Chris Spirou, former chairman of the New Hampshire Democratic Party and a friend of Biden, in a related New York Times article.

Biden is extending his initial early October deadline for a candidacy decision and is not expected to make the trip to Nevada, the Daily Mail reported, even though the vice president convened a meeting of family members and advisors this past weekend.

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James Carville, Bill Clinton’s former campaign strategist, was quoted in the New York Times article, “Biden knows what running for president entails. He knows what being president entails. If you want to run, run. … The clock is ticking.”

According to a compilation of major, recent polls, the Daily Mail states that Clinton enters Tuesday's debate still in the top spot at 42 percent, a commanding lead over both Sanders and Biden, who poll at 25.4 percent and 18.6 percent respectively.

Tuesday's debate is scheduled to air at 8:30 p.m. Eastern time on CNN.