Washington (CNN)Bernie Sanders, the Vermont senator currently rising in polls against Hillary Clinton as they vie for the Democratic presidential nomination, responded to critics who say he hasn't done enough to appeal to non-white voters during his raucous rally in Madison, Wisconsin, on Wednesday.
Bernie Sanders adds race, civil rights to his stump speech
"All of you are aware of the tragic history of racism in America," Sanders said to a predominantly white audience on around 10,000 people. "But for a very long time, African-Americans and their white allies came together and they struggled and they stood up for justice and they stood up to lynching and they stood up to segregation and the stood up to a nation where African-Americans couldn't even vote in America."
Sanders added, "And change came about, not as much as we would want."
The new refrain came during a portion of Sanders' stump speech where the senator speaks at length about the slow process of change.
"All of you who are here this evening, I think, have an understanding about how real change takes place in our country and has historically taken place," Sanders said. "You are aware that change takes place from the bottom on up. It is never from the top on down. People on top are usually the last to know."
The new focus on race relations comes at a time when the country as a whole has turned it's attention to such issues, in the wake of the Charleston massacre and a series of police-related deaths of African-Americans.
Sanders also turned his comments on race and the fight for civil rights into a case for more economic equality.
"So as a nation, we have a right to be very proud of the successes that we have seen because of the struggle of millions of people to create a less discriminatory society. That is something we should be proud of," Sanders said. "But there is one struggle in which not only have we not succeeded but in which we are losing ground and that is the fundamental struggle for economic justice."
A CNN/ORC poll released last month found that 5% of non-white voters supported Sanders for president, compared to 10% of overall voters who support the independent senator. Other polls have found Sanders similar results.
Sanders' aides contend that the senator doesn't do well with non-white voters because he represents a state that is 95% white and his history as a fight for civil rights is not well known. And they have pushed back against critics, pointing out that Sanders' organized sit-ins against segregation and attended the 1963 March on Washington.
"I have a long history in fighting for civil rights. I understand that many people in the African-American community may not understand that," Sanders said during an interview last month.
Wednesday in Madison, Sanders also made overtures to the electorate the launched President Barack Obama into the White House, one that was far more diverse than Sanders' base supporters.
The senator heralded Obama's recent move to change overtime laws, calling the decision "overdue."
And in one of the bigger applause lines of the night, Sanders said the audience should be proud of electing Obama in 2008.
"We know that we still have racism in America," he said. "But as a nation, we should be proud that in 2008, we elected the first African-American to be president of the United States."