Republican presidential candidate Michele Bachmann Thursday likened the conservative movement to the Civil Rights movement, a comparison that some may find offensive.

"Of any election, this is the one where conservatives don't have to settle," the candidate said at an Orlando rally organized by Ralph Reed's Faith and Freedom Coalition.

"President Obama's approval numbers are the lowest they've ever been, and I am here to tell you, they are going lower further," she added. "So we don't have to go to the side, we don't have to sit on the back of the bus in this election. We need to stand up and be counted and have a candidate who is truly a social conservative who will stand for our issues."

The phrase "back of the bus" is associated with African Americans' struggle for equal rights. In the 1950s, Montgomery, Alabama reserved the front of public busses for white riders, while blacks had to move to the rear. Rosa Parks sparked a bus boycott when she refused to give up her seat for a white passenger.

In 2009, the polling organization Gallup found that only 2 percent of the Republican Party identified themselves as black.

Using the phrase "back of the bus" wasn't a one-time slip for Bachmann. She repeated it again the next day at the Conservative Political Action Conference in Orlando.