"Leadership is about more than the legislation one sponsors and the votes one casts. On Thursday night, Sen. Kirk's comments about his opponent's heritage were deeply offensive and racist. His attempt to use Congresswoman Tammy Duckworth's race as a means to undermine her family's American heritage and patriotism is beyond reproach," Griffin wrote, adding that Kirk's tweeted apology "failed to adequately address the real harm and magnitude of his words."