"Martin had a dream, and Cesar and Dolores said, 'Sí se puede,'" said vice presidential nominee Tim Kaine.
That's a phrase you've heard a lot at the Democratic National Convention.
"Sí se puede" literally means "Yes, it can be done," or "Yes, we can" for short. Sound familiar?
"Sí se puede," said President Barack Obama during his 2008 campaign at a conference for Latino leadership.
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But before it was a campaign slogan, it was a rallying call for labor rights.
"Sí se puede" was first used in the '70s by the United Farm Workers union in Arizona. Cesar Chavez and Dolores Huerta used it to motivate farm workers to demand fair wages, pensions, medical benefits and better hours and working conditions.
This video includes images from Getty Images and Library of Congress / Marion S. Trikosko. Music provided courtesy of APM Music.