Sen. Marco Rubio (R-Fla.) has written an op-ed for Breitbart, a publication he blasted during the Republican presidential primaries as "not a credible source."

"We don't even credential them for our events," Rubio told Fox News in February 2016. "This is the same website that reported that Fox News and that you and your guys in the debate gave me the questions so that I could prepare. You know that that's not true. So I literally don't even talk about the things they report because they're basically conspiracy theories and oftentimes manipulated."

Breitbart rose from the relative fringes along with then-candidate Donald Trump, often giving him positive coverage during the campaign. Stephen Bannon, the publication's one-time chairman, now works as the president's chief strategist.

Rubio's op-ed pitches Breitbart readers on "tax reform that empowers families."

"We must ensure comprehensive tax reform includes specific and meaningful tax relief for parents," Rubio wrote. "After all, families are the fundamental building blocks of our communities, and the health of our society depends on families being able to provide safe and secure homes, raise active citizens, and love their children unconditionally in ways no other social institution can. Families are how values are passed on from generation to generation. We simply cannot have a strong nation without strong families." Jeva Lange