WASHINGTON, Nov 27 — Bernie Sanders is talking and acting like a once and future US presidential candidate, telling a magazine he will "probably run” in 2020 if he sees himself as the Democrats’ best chance to defeat Donald Trump.

The popular US senator and self-declared Democratic socialist also has just written a book, entitled "Where We Go from Here,” that lands this morning, the same night he delivers a speech at George Washington University in the capital.

Sanders, 77, launched an extraordinary run for the 2016 Democratic nomination, and while he came up short against Hillary Clinton many Sanders supporters express confidence that he could have beaten Trump for the White House.

Sanders said he still believes his ideas are best for the nation, but is not openly campaigning for the nomination.

"I’m not one of those sons of multimillionaires whose parents told them they were going to become president of the United States,” he told New York magazine in a piece released late Sunday.

"I don’t wake up in the morning with any burning desire that I have to be president.”

Sanders is widely thought to have popularised liberal positions such as Medicare for all, in which the national health insurance for people 65 and over is expanded to everyone, and a US$15 (RM62.82) minimum wage.

And who else would be as effective a messenger for such a platform as Sanders himself?

"If there’s somebody else who appears who can, for whatever reason, do a better job than me, I’ll work my ass off to elect him or her,” he said.

But "if it turns out that I am the best candidate to beat Donald Trump, then I will probably run,” Sanders added.

The 2020 election is still 101 weeks away. But many candidates announce their intentions early in the year prior to the election.

Sanders would likely face intense competition. Several other Senate Democrats are considering presidential bids, including Cory Booker, Sherrod Brown, Kamala Harris, Amy Klobuchar and Elizabeth Warren.

Mayors like New York’s Bill de Blasio and Eric Garcetti of Los Angeles are also in the mix, as are former vice president Joe Biden, New York billionaire and former mayor Michael Bloomberg, and Texas congressman Beto O’Rourke, who lost his recent bid to oust Republican Senator Ted Cruz. — AFP