Don’t be led astray by the humble, “I’m still thinking about running” mantra parsing from Sen. Bernie Sanders’s lips: the man wants to be president. While speculation continues over whether the septuagenarian will decide to launch a second consecutive presidential campaign, the early tea leaves point in the direction of Vermont’s senior senator declaring his candidacy sometime in the early months of 2019.

The bigger question for anyone willing to write about it is not whether Bernie Sanders will run again - it’s whether he has enough fuel in the tank to get him across the finish line.

This has nothing at all to do with age (he’s a spry 77 years young) and everything to do with his star appeal. With so many Democrats in Washington and around the country seeing images of themselves kicking President Trump out of the White House, Sanders will have to find a way to both recapture the magic of his previous underdog campaign while broadening his appeal to Democratic constituencies he struggled with.

During the 2015-2016 campaign, Bernie was fortunate to have the entire progressive lane to himself. The 2016 Democratic presidential field was an underwhelming list of has-been politicians like Jim Webb and jokesters like Lincoln Chafee. Hillary Clinton represented the quintessential establishment, big-money candidate, a woman who had a highly impressive resume but reeked of the status-quo, same-old politics many voters were tired with. Sanders may have looked like a mad scientist who gladly talked about blowing up Wall Street, but he was the only person in the primary who anti-Clinton, anti-establishment Democrats could support.

Sanders will not have that luck in 2020. The contenders haven’t started declaring their candidacies, but anyone with a half a brain can see that the Democratic field will likely be the party’s largest ever. Bernie won’t be the only true-blue progressive in the race; Elizabeth Warren, Sherrod Brown, Cory Booker, Tom Steyer, Kamala Harris, Amy Klobuchar, Cory Booker, and even Joe Biden are all either self-proscribed unapologetic liberals or figures who possess some progressive characteristics. Die-hard Bernie loyalists will likely stick with him in 2020, but others who threw their votes to the senator because of their anti-Clinton animus will have a pool of alternatives to choose from.

Minority voters will also remain a problem for Sanders if he decides to run one more time. If voters under 30 were his core constituency in 2016, African-American voters in the South were his kryptonite. Hillary Clinton won about 70 percent of the African-American vote in states with the biggest African-American populations. In South Carolina, Sanders claimed a pathetically low 14 percent of African-Americans. With a number of appealing African American candidates likely entering the 2020 race (Harris, Booker, and Deval Patrick among them), it’s safe to say the old white guy from Vermont will probably continue to struggle with this demographic.

None of this may stop Bernie Sanders from believing he can surmount all of these setbacks and win the Democratic nomination on his second try. But his advisers would be fools not to opine whether their boss’s moment has passed.

Daniel DePetris (@DanDePetris) is a contributor to the Washington Examiner's Beltway Confidential blog. His opinions are his own.