He's upset with liberals who are opposing President Donald Trump's pick for Attorney General.
The Texas Senator went on Fox News Wednesday defending his colleague Senator Jeff Sessions.
Cruz said, "listen, the Democrats are the party of Ku Klux Klan. You look at the most racists, you look at...the Dixiecrats, they were Democrats who imposed segregation, imposed Jim Crow laws."
Sessions has been dogged by allegations of racism by the left during his confirmation hearings.
Senate Democrats staged an all night protest Tuesday night against Sessions' nomination.
Cruz argued that the left accuses people of being racist when they don't have any other arguments.
RELATED: KKK throughout history
Ku Klux Klan (KKK) throughout history
Ku Klux Klan (KKK) throughout history
1866: A wood engraving depicting two members of the Ku Klux Klan. The white sheet and hood were supposed to represent the ghosts of Confederate soldiers risen from the dead to seek revenge. (Photo by MPI/Getty Images)
UNITED STATES - JANUARY 01: Kayne Township. Ku Klux Klan Wedding In New Jersey. (Photo by Keystone-France/Gamma-Keystone via Getty Images)
(Original Caption) Long Island, NY-Ku Klux Klan with hands raised in oath during night meeting.
20th March 1922: Members of the white supremacist movement, the Ku Klux Klan standing by an aeroplane, out of which they dropped publicity leaflets over Washington DC. (Photo by General Photographic Agency/Getty Images)
(Original Caption) 1/4/1923-Homestead, FL: Photo shows gathering of the Ku Klux Klan, members of the invisible empire, at Homestead, FL., thirty miles South of Miami, and within three miles of the Southern most point of the mainland of the United States. The Imperial Wizard of he Klan is somewhere in the group. But, he just won't make himself known.
Ku Klux Klan members hold a march in Washington, DC, on August 9, 1925.
UNITED STATES - JANUARY 01: Ku Klux Klan Ritual At Atlanta In Usa During Thirties (Photo by Keystone-France/Gamma-Keystone via Getty Images)
(Original Caption) Over 100,000 people are expected in Washington for the Klan parade and gathering. Government buildings are all guarded in case of disorder. Photo shows members of the Women's K.K.K. of Virginia marching down Pennsylvania Ave.
5/07/98 PHOTOGRAPHER: Susan Biddle - TWP Wheaton, Md. BRIEF DESCRIPTION: Darryl Davis and his KKK collection Davis, a blues pianist, meets as many KKK guys as he can to find out why they are as they are. He has a collection of robes and other KKK items such as this medallion. (KU KLUX KLAN) (Photo by Susan Biddle/The Washington Post/Getty Images)
A young protester argues with Thom Robb during a Ku Klux Klan rally in Stephenville, Texas. Robb is the national director of the Arkansas-based Knights of the Ku Klux Klan. (Photo by ?? Greg Smith/CORBIS/Corbis via Getty Images)
The Imperial Wizard of the National Knights of the Ku Klux Klan, Don Black, wearing a suit and tie, with white-gowned Klan members in the background.
UNSPECIFIED - CIRCA 1754: Ku Klux Klan members supporting Barry Goldwater's campaign for the presidential nomination at the Republican National Convention, San Francisco, California, as an African American man pushes signs back: 12 July 1964. Photographer: Warren K Leffler. (Photo by Universal History Archive/Getty Images)
UNSPECIFIED - CIRCA 1754: Parade of the Ku Klux Klan, in regalia and carrying the stars and stripes, through counties of Virginia bordering on the District of Columbia, America, 1926. (Photo by Universal History Archive/Getty Images)
Ku Klux Klan members march through downtown Houston under heavy police protection. (Photo by Greg Smith/Corbis via Getty Images)
(Original Caption) The Ku Klux Klan failed to make good its threat to parade through the streets of this town today and instead had a small parade in Neptune City and Neptune Township. Less than 3,000 men, women, and children marched in the parade, headed by Arthur H. Bell, Grand Dragon of the Realm of New Jersey. Some of the Klansmen were robed and masked, others wore their robes with hoods lifted. (Photo by George Rinhart/Corbis via Getty Images)
Members of the Ku Klux Klan attend a demonstration in Lawrenceburg, Tennessee. They are protesting against the Martin Luther King holiday. (Photo by mark peterson/Corbis via Getty Images)
Demonstration of the Ku Klux Klan (Photo by F. Carter Smith/Sygma via Getty Images)
UNITED STATES - OCTOBER 23: Jeffery Berry, national imperial wizard of the Knights of the Ku Klux Klan (l.), Grand Dragon James Sheehy (nursing his would after being attacked), and other Klan members hold a rally at Foley Square near the New York State Supreme Court House. (Photo by Budd Williams/NY Daily News Archive via Getty Images)
VALLEY FORGE, PA - SEPTEMBER 25: A Ku Klux Klan member shows off his tattoo during an American Nazi party member during American Nazi Party rally at Valley Forge National Park September 25, 2004 in Valley Forge, Pennsylvania. Hundreds of American Nazis from around the country were expected to attend. (Photo by William Thomas Cain/Getty Images)
SHARPSBURG, MD - SEPTEMBER 07: Members of the Confederate White Knights hold a flag during a rally at the Antietam National Battlefield September 7, 2013 near Sharpsburg, Maryland. The Rosedale, Maryland Ku Klux Klan group held the rally to protest against the administration of President Barack Obama and the U.S. immigration policies. (Photo by Alex Wong/Getty Images)
COLUMBIA, SC - JULY 18: Ku Klux Klan members take part in a Klan demonstration at the state house building on July 18, 2015 in Columbia, South Carolina. The KKK protested the removal of the Confederate flag from the state house grounds, as law enforcement tried to prevent violence between the opposing groups. (Photo by John Moore/Getty Images)
Demostrators take part in a protest against asylum seekers brought to stay at a former army barracks in the Hennala district in Lahti late September 24, 2015. Demonstrators threw stones and launched fireworks at a bus full of asylum seekers arriving at a reception centre in Lahti in southern Finland, late on Thursday, Finnish media reported on Friday. Between 30 and 40 demonstrators, one in a white robe like those worn by the white supremacist Ku Klux Klan in the United States, waved the Finnish flag and shouted abuse at the bus. Picture taken September 24, 2015. REUTERS/Heikki Ahonen/Lehtikuva ATTENTION EDITORS - THIS IMAGE WAS PROVIDED BY A THIRD PARTY. FOR EDITORIAL USE ONLY. NOT FOR SALE FOR MARKETING OR ADVERTISING CAMPAIGNS. THIS PICTURE IS DISTRIBUTED EXACTLY AS RECEIVED BY REUTERS, AS A SERVICE TO CLIENTS. NO THIRD PARTY SALES. NOT FOR USE BY REUTERS THIRD PARTY DISTRIBUTORS. FINLAND OUT. NO COMMERCIAL OR EDITORIAL SALES IN FINLAND.