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The New York City mayors club could not be more splintered.

As one former mayor runs for president and the other one unflinchingly supports the current president, the New York City mayor who's actually in power today has decided to go with a third option. Bill de Blasio, once a 2020 Democratic contender himself, plans to endorse Sen. Bernie Sanders (I-Vt.) for the presidency, and will soon join him to campaign in Nevada, Politico and The New York Times report.

De Blasio campaigned on a progressive presidential platform of his own for a few months last year until dropping out with no traction to speak of. But even though he's positioned himself as a far-left leader throughout his mayoral terms, de Blasio waited until Sanders won the first two 2020 contests in Iowa and New Hampshire before going all in. When exactly de Blasio will announce his endorsement is unclear, but he is expected to head to Nevada on Sunday to start campaigning around the country.

A cross-country tour isn't an unsurprising move for de Blasio, who seemed to be over his mayoral duties and New York City as a whole when he started his 2020 run last year. This reported endorsement of course puts de Blasio at odds with fellow former New York City Mayor Michael Bloomberg, who is running a more centrist 2020 campaign than Sanders. The mayor before Bloomberg, President Trump's ally Rudy Giuliani, is of course way, way further to the right.