President Donald Trump explicitly condemned hate groups who harbor racist beliefs after getting panned by both sides of the aisle for failing to adequately condone such alt-right groups in wake of violent clashes in Charlottesville, Virginia that left one dead on Saturday.

"Racism is evil," Trump said. "And those who cause violence in its name are criminals or thugs, including the KKK, neo-Nazis, white supremacists and other hate groups that are repugnant to everything we hold dear as Americans."

The remarks came nearly 48-hours since the president first addressed the event without specifically condemning the alt-right groups involved in the rally – a decision that set off a firestorm of pushback not only from Democrats and civil rights organizations, but also from a slate of GOP lawmakers.

The Republican Party was founded by Abraham Lincoln, but has had a checkered relationship on race issues in the past. That said, many leaders have forcefully spoken out against racism and its place in the party.

George W. Bush addressed racism and the Republican Party head-on when he spoke to the NAACP's annual convention in 2000, ahead of the election that would vault him to the presidency.

"For our nation, there is no denying the truth that slavery is a blight on our history, and that racism, despite all the progress, still exists today," Bush said at the conference in Baltimore. "For my party, there is no escaping that the reality that the party of Lincoln has not always carried the mantle of Lincoln."

He continued: "Recognizing and confronting our history is important. Transcending our history is essential."

In the speech, Bush outlined sweeping policy proposals for education, housing and health care, and promised that, if elected president, he would enforce civil rights laws and call out discrimination.

"Discrimination is still a reality, even when it takes different forms," he said. "Instead of Jim Crow, there is racial redlining and profiling. Instead of separate but equal, there is separate but forgotten."

When President Ronald Reagan addressed the group in 1981 he said those who are racist are out of step with American values.

"A few isolated groups in the back order of American life still hold perverted notions of what America is all about," Reagan said while addressing the NAACP convention in Denver.

"Recently in some places in the nation, there's been a disturbing reoccurrence of bigotry and violence," he said. "To those individual who persist in such hateful behavior … you are the ones who are out of step with our society, you are the ones who willfully violate the meaning of the dream that is America, and this country because it does what it stands for will not stand for your conduct."

Later, Bob Dole, in his 1996 presidential nomination acceptance speech at the Republican National Convention in San Diego, was even more direct.