"If he doesn't understand why 'white supremacy' is offensive, he should find another line of work," McConnell said.
Fox News covered King's comments for just 42 seconds the day after they were revealed in the New York Times report.
Iowa Senator Joni Ernst condemned King's comments on white supremacy as "offensive" and "racist."
Recently re-elected Iowa Republican Representative Steve King was caught on tape ridiculing Mexico and immigrants in audio he previously had denied existed.
Republican Representative Steve King of Iowa has won a ninth term after narrowly defeating his Democratic challenger, J.D. Scholten.
Author Stephen King said he had "personal reasons" for wanting Iowans to vote Rep. Steve King out of office.
King has been isolated due his support of white nationalists.
A prominent Democratic senator once made the same proposal in 1993–and later apologized for it.
Republican Representative Steve King met with a publication tied to the Freedom Party of Austria, which was founded by a former Nazi SS officer.
"Idiot congressman who failed history," one user wrote. "Fascism is nothing at all like socialism and fascists killed socialists in Italy and Germany."
This isn't the first time King has shared content on Twitter from people or organizations with white nationalist ties.
"I have no idea what he was thinking," Ira Mehlman, media director for the Federation for American Immigration Reform, said of President Donald Trump.
Steve King said that "we can't restore our civilization with somebody else's babies."