Editor's note: Thomas Maier is the author of "The Kennedys: America's Emerald Kings," (Basic Books), which was the basis of a Warner Bros. video documentary released in November. He is a reporter for Newsday. Thomas Maier says Ted Kennedy's immigrant heritage helped drive his advocacy of a more open America. (CNN) -- With a sign from Dunganstown, Ireland, hanging in his U.S. Capitol office, a reminder of the famine-ravished farm where his ancestors began, Sen. Edward "Ted" Kennedy always seemed to understand that the Kennedys were perhaps America's greatest immigrant story -- overcoming religious, ethnic and cultural barriers to reach once unimaginable heights.
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Thomas Maier: Kennedy's heritage was of an immigrant family that broke barriers
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Maier says the Kennedy brothers pushed wider opening of U.S. borders in 1960s
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He says resulting demographic change helped usher in President Obama's election
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Maier: Like JFK, Obama's background is much different than other presidents
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Edward "Ted" Kennedy
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Kennedy
@placeholder went back to Ireland many times, including to the old Kennedy homestead in Dunganstown.
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The culmination of this Kennedy's immigrant legacy was most apparent by the 2008 presidential campaign, which offered many reminders for Ted Kennedy of the barriers his brother faced in 1960, becoming the first @placeholder president from a minority background.
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Obama
As a minority, born to black and white parents, @placeholder had to overcome code words and subtle biases historically applied to African-Americans.
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America
From the broadest vantage, the Kennedy story reminds us of the glories and the limits of @placeholder's melting pot and those histories that paint people from minority groups in familiar "just like us" tones.