Al Gore is expected to begin campaigning in support of Hillary Clinton’s bid for the presidency, urging young people to vote and promoting climate change as a generational issue.

According to a report in the Washington Post Tuesday night, Gore is also expected to speak about third party dynamics in presidential campaigns.

With polls showing Gary Johnson and to a lesser extent Jill Stein drawing more votes from Clinton than Trump in a still-close race, Gore’s presence brings echoes of the 2000 race. Gore lost the decisive state of Florida to George W. Bush by a mere 537 votes while third party candidate Ralph Nader pulled in nearly 100,000 votes in the state.

When he endorsed Clinton for the presidency in July, Gore tweeted: “Given her qualifications and experience—and given the significant challenges facing our nation and the world, including, especially, the global climate crisis, I encourage everyone else to do the same.”

The millennials Clinton hopes to court with Gore’s global warming message may not remember the first Clinton presidency. They may, however, remember Gore’s film, “An Inconvenient Truth,” and his Nobel Peace Prize, awarded in 2007.

Gore is one in a long list of powerhouse Clinton surrogates that includes both the President Barack Obama and First Lady Michelle Obama, former President Bill Clinton, and, increasingly, former members of the George W. Bush administration.

This post has been updated.