The “Take Our Border Back Southern Border Convoy” has been amplified and celebrated by right-wing media and political figures as posts promoting it have spread across social media.

Robert F. Kennedy Jr., a scion of one of the country’s most famous Democratic families, on Monday dived into the full embrace of a host of conservative figures who eagerly promoted his long-shot ...

Spanish-language radio shows and social media posts echoed false narratives about the now-dead border deal that originated in English-language conservative media, researchers said.