It actually means one man, Andrés Manuel López Obrador, and his faithful and intollerant followers.
IMO he's no leftist, really. More of a Nacionalist.
Any one who disagrees with him is either a "member of the mafia" or a traitor.
He created his own party, Morena, where he plays as God.
He has no feasonable program, but is close to Venezuelan style "anti-imperialism". His economic policy is giveaways and subsidies.
He reaps on understandable public discontent. And discontent is growing.