For generations young people left on boats and planes, primarily to England and America, not by choice but by necessity. Most found a welcome in their new environments. And when they didn't they displayed ingenuity and resourcefulness. New York University history lecturer Linda Dowling Almeida points out that the mid-19th-century Irish immigrants used the clout of urban political machines and leadership by the Catholic church to beat back a nativist movement that saw them as a threat to national security and American culture.

In the 1980s and 1990s the Irish achieved extraordinary success in lobbying with the creation of thousands of "special" visas. Such was their track record in tapping into power that immigration historian Roger Daniels described it to the New York Times as " affirmative action for white Europeans".

Today there are only between 25,000 and 50,000 Irish illegals across America - the last generation of a different country. Fighting for a voice for them is the Irish Lobby for Immigration Reform led by Niall O'Dowd, publisher of the Irish Voice, who yesterday brought their campaign home to Dublin for a rally.

More than 34 million Americans trace their heritage to Ireland and, despite their dwindling numbers, this is what the undocumented Irish are counting on. Democratic presidential hopefuls Hillary Clinton and Barack Obama are just two of a host of senior politicians who have added their voices to the campaign.

It's generally accepted that a special measure for the Irish would be hard to swing. The first step will be to get an immigration reform bill approved by congress by the end of this year. The democratic victory in last November's congressional elections improves that prospect. And ultimately the Democrats' need to count on Irish American swing voters could be the best hope the illegal Irish have for a special arrangement.