Massachusetts Rep. Joe Kennedy III, seen as a rising political star with a famous last name, will deliver the Democratic response to President Trump's State of the Union on Tuesday.Top Democratic leaders in Congress made the announcement Thursday evening, calling Kennedy a "relentless fighter for working Americans." Kennedy is the grandson of the late Robert Kennedy, the former U.S. attorney general and New York senator who was assassinated in 1968. He is also the great nephew of both the late Massachusetts Sen. Edward Kennedy and the late president John F. Kennedy."While President Trump has consistently broken his promises to the middle class, Congressman Kennedy profoundly understands the challenges facing hard-working men and women across the country," House Democratic Leader Nancy Pelosi, D-Calif., said in a statement.Although Kennedy has served in Congress since 2013, the 37-year-old has kept a relatively low political profile.On Friday, Kennedy tweeted he was honored to be selected to give the rebuttal.Responding to rumors that he's interested in running for higher office, Kennedy told Boston Globe shortly before the announcement about the State of the Union speaking slot that he was focused on his current job."I don't give a whole lot of thought or credence to questions about what comes on next, what goes on next," he added. "My life is busy enough at the moment that I don't even really know where I'm having lunch today."Aside from his famous surname, Kennedy is not well known outside of Massachusetts. But, at least for a few minutes, his role as rebutter-in-chief will make him the face of a Democratic Party hoping to make big gains in midterm elections later this year.He'll deliver his address from Diman Regional Vocational Technical High School in Fall River, Mass., about an hour south of Boston, before an audience of students and other members of the community.The Herald News quoted Kennedy as saying the city of Fall River is "resilient and proud," adding: