Bennett donated more than $1.1 million to Donald Trump's presidential campaigns and to the Republican National Committee between the 2016 election and May 2020. He has been a supporter of Texas Governor Greg Abbott. He is active in the school privatization movement and in efforts to elect more conservatives to school boards. He has been on the advisory boards of Texans for Education Reform and Texans for Education Rights. A 2023 article in The Real Deal about Bennett's increased activities in politics and media said that he has "engaged in many political battles, and won quite a few", particularly relating to local issues in Texas. He backed the proposed Dallas HERO ballot measures in 2024 to make major changes in Dallas city government. Of the three measures, two passed: the first removed sovereign immunity, making it easier to sue the city for breaking laws, while the second would require the city to hire 900 additional police officers.

Bennett is the publisher of the Dallas Express, a conservative news website launched in 2021 in Dallas, Texas, that is unrelated to the African-American Dallas newspaper of the same name that published from 1892 to 1970. In October 2020, The New York Times reported that Bennett had pitched a media network run by Brian Timpone to publish articles about topics ranging from COVID-19 stimulus legislation to U.S.–China policy. Bennett announced his acquisition of the Dallas Express in February 2021. That year, Bennett sued The Dallas Weekly, alleging libel over its unfavorable descriptions of the new Dallas Express, but the case was dismissed on appeal in 2022 in Monacelli v. Bennett.