Manchin and Sinema: Describing them as "centrists" is a misnomer.

 A better term for them would be "self-centered obstructionists".

From The Guardian -

Joe Manchin and Kyrsten Sinema: the centrists blocking Biden’s agenda

 

Donald Trump’s favorite insult for political opponents inside his own party is “Rino” – Republican in name only. By such logic, Senators Joe Manchin of West Virginia and Kyrsten Sinema of Arizona are the epitome of Dinos, two elected Democrats whose dogged resistance to Joe Biden’s social agenda threatens/threatened to upend his entire presidency.

Their standoff with the party’s progressive wing over the price tag of Biden’s ambitious reform package has become almost more of a hazard to his legacy than anything the Republicans, currently in a narrow minority in both chambers of Congress, can throw at it.