Memphis, Tennessee (CNN) -- Forty-two years ago, the Rev. Martin Luther King Jr. was assassinated in Memphis, Tennessee, while promoting the importance of the content of one's character. Today, an African-American candidate who marched with King is hoping the voters in a Democratic primary race will look at the color of his skin. Willie Herenton, who served as mayor of Memphis for almost two decades until he resigned in 2009, is making race a key part of his platform in his attempt to unseat incumbent Rep. Steve Cohen. Herenton's main campaign slogan on yard signs, flyers and T-shirts is the phrase "Just One," a reference to his belief that there should be at least one African- American representing Tennessee in Congress.
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Willie Herenton hopes voters in Tennessee's 9th District will look at color of his skin
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Herenton challenging incumbent Rep. Steve Cohen in Democratic primary
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Cohen has backing of Obama, Congressional Black Caucus
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Both candidates say they think Martin Luther King Jr. would be proud of their work
"Congressman Cohen is a proven leader in the United States Congress and a strong voice for @placeholder," the statement said.
"Together, we passed historic health care reform, and together we're continuing the fight to renew our economy and bring jobs back to the @placeholder people.