By the time 2020 rolls around, Bernie Sanders will be on the cusp of his ninth decade on earth.
But that hasn't stopped the Vermont senator and runner-up in 2016's Democratic primaries from mulling another presidential bid in four years.
"Four years is a long time from now," Sanders said. "We'll take one thing at a time, but I'm not ruling out anything."
Sanders noted that he's up for re-election in 2018, The Associated Press reported, and that campaign could serve as a warm-up should Sanders decide he wants to run for president again.
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But if he does attempt a second run for the White House, Sanders would be the potentially oldest president in history -- by a margin of 10 years.
The late Republican President Ronald Reagan held the record for oldest newly-elected president, taking office two weeks shy of his 70th birthday. Now that distinction goes to President-elect Donald Trump, who celebrated his 70th birthday in June.
Despite his age, Sanders had no problem whipping up sustained enthusiasm from young voters, who responded to his ideas and policy platforms -- including free college tuition, an increase in the minimum wage, and efforts to limit the impact of money in politics.
Sanders trounced his primary rival, former Secretary of State Hillary Clinton, among young voters, earning as much as 80 percent of the vote from people 30 years old or younger in some states, according to a Washington Post analysis. During the primaries, he tallied more than 2 million votes from that age group, which was more than Clinton and Trump combined.
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The Vermont senator told The Associated Press that he's disheartened by Trump's election day win, but he placed the blame on his own party.
"It is an embarrassment, I think, to the entire Democratic Party that millions of white working-class people decided to vote for Mr. Trump, which suggests that the Democratic message of standing up for working people no longer holds much sway among workers in this country," Sanders said.
While he avoided directly criticizing Clinton, Sanders told the AP that a "lack of enthusiasm" translated to fewer people coming out to vote for Democrats. That was one of Clinton's weak points during the long campaign, with many pundits calling her the "safe" choice for Democrats.
Sanders also took aim at Clinton's biggest donors -- Wall Street firms and their executives.
"You cannot be a party which on one hand says we're in favor of working people, we're in favor of the needs of young people but we don't quite have the courage to take on Wall Street and the billionaire class," he said. "People do not believe that. You've got to decide which side you're on."