Business Insider's John Haltiwanger described Charlie Kirk and Turning Point USA in a January 2019 interview as such:
Charlie Kirk, the president and founder of the conservative advocacy group Turning Point USA, is rapidly becoming one of the most prominent figures on the right today. Kirk's organization is popular among young conservatives but has been tied to several controversies and faced accusations of racial bias.
Carpe Donktum, a stay-at-home dad from Kansas who doesn't use his legal name, is pictured above, left, with the One America News Network host Jack Posobiec.
Donktum is a self-described "eternally Sarcastic Memesmith specializing in the creation of memes to support President Donald J. Trump."
They’re Blockbuster. We’re Netflix. pic.twitter.com/WR28HNql3b
PragerU is a right-wing YouTube channel operated by the conservative commentator Dennis Prager that specializes in short educational videos with a conservative bent.
The Southern Poverty Law Center describes PragerU as such:
Founded as a nonprofit by conservative talk radio host Dennis Prager in 2009, PragerU's "5 Minute Ideas" videos have become an indispensable propaganda device for the right. More than a few similarly function as dog whistles to the extreme right.
Garrison, a political cartoonist with conservative views, has been criticized by the Anti-Defamation League for producing "blatantly anti-Semitic" cartoons. He was initially invited to the summit by the White House, and then disinvited over those very cartoons.
Official Statement from Ben Garrison on the White House Social Media Summit pic.twitter.com/4UVbpi0uRK
Project Veritas is a nonprofit founded by James O'Keefe, best known for undercover videos and other operations trying to expose liberal bias at media and tech companies — including one incident where the organization appeared to be plotting to place a fake story in The Washington Post, the newspaper reported.
Tennessee Sen. Marsha Blackburn is a hard-line conservative who has supported a variety of controversial policies in the past, from a 2009 "birther" bill to Trump's 2017 immigration ban.
Similarly, Florida Rep. Matt Gaetz is a Republican with extremely conservative views on gun policy, immigration, and climate change.