I quote that saying as it is given in that Quoteland.com blog and at a number of other places:

"Rosa sat so Martin could walk, Martin walked so Obama could run, Obama ran so our children can fly!"

-snip-

Although apparently it was earlier stated as "Rosa Parks sat down so we could stand up. Martin Luther King marched so Jesse Jackson could run. Jesse Jackson ran so Obama could win."

It's going to be interesting to see if and how this saying changes over time.