A three-term Iowa state senator says he plans to challenge longtime U.S. Rep. Steve King in next year’s Republican primary.

King has long been dubbed "America's white supremacist congressman" for often making remarks in support of white nationalism. “White nationalist, white supremacist, Western civilization — how did that language become offensive?” King asked in an interview with The New York Times published on Thursday. “Why did I sit in classes teaching me about the merits of our history and our civilization?”

Conservative pundit Ben Shapiro responded to King's quote saying, "Congress ought to vote to censure him, and then he ought to be primaried ASAP. …" Shapiro also tweeted he will donate to his primary opponents campaign.

Randy Feenstra, an assistant Republican legislative leader, announced Wednesday he intended to run for the northwest Iowa seat and has opened a federal campaign committee.

Without mentioning King by name, Feenstra said the district doesn’t have a voice in Washington “because our current representative’s caustic nature has left us without a seat at the table.” He added Iowans don’t need more “sideshows or distractions.”

King just began his ninth term. He’s known for hardline views on immigration, abortion and gun rights. Democrats and sometimes Republicans have criticized his blunt comments.

King has typically won re-election easily in the solidly Republican district but narrowly defeated his Democratic opponent in November.