"She's not from Ky," Groob said in a reply to a tweet questioning her attack. "She is Asian and Bush openly touted that."
As the controversy grew on social media, a statement was released on the Kentucky Democratic Party's Twitter account, denouncing the comments.
"These comments are abhorrent and have no place in Kentucky politics. We strongly denounce them," the statement read.
"My sincere apologies for poor choice of words," Groob tweeted about 15 minutes later.
Though Groob has deleted the tweets which mentioned Chao's ethnicity, several others about Chao remain.
"If Mitch McConnell is going to bring his wife in the race, then her lack of KY status is fair game," Groob tweeted.