Brendan Boyle will become the only member of Congress with an Irish-born parent, after being elected to the House of Representatives in Tuesday's US mid-term elections.
Mr Boyle (37), the son of an emigrant from Glencolmcille in the Donegal Gaeltacht, was elected in a Democratic stronghold covering Philadelphia and suburbs surrounding the city.
The three-term state representative beat Republican Dee Adcock in Pennsylvania's 13th District with more than 67 per cent of the vote, after seeing off a strong Democrat challenge from former congresswoman Marjorie Margolies, the mother-in-law of Chelsea Clinton, in a closely-watched primary election in May.
Mr Boyle’s win was the biggest Irish victory in these US elections in a campaign that played heavily on the working-class story of his Irish father Frank, a janitor on Philadelphia’s rail transit system.
He was almost joined in Washington by Republican Ed Gillespie, another son of a Donegal emigrant, who nearly unseated Virginia's Democrat Mark Warner in an unexpectedly close Senate race.
The Irish Times
last week, Mr Boyle said he had spoken with Democratic House leader
and minority whip
about a role on the House foreign affairs committee, where he hopes to maintain interest in the Northern
In a setback for the presidential hopes of Maryland’s Irish-American governor, Martin O’Malley, he was unable to ensure a continued Democratic presence in the State House in Annapolis.
His anointed would-be successor Anthony Brown, state lieutenant governor, was beaten by Republican Larry Hogan by 54 per cent to 45 per cent in a shock defeat, as voters in a state that has backed Democrats in the last six presidential elections turned against Mr Obama's party.
The defeat was a rejection of Mr O’Malley’s eight-year tenure in a state that is home to many government workers and political staffers in Washington DC, and a reflection of the scope of the Republican gains and anti-incumbent sentiment.
Mr Brown received strong backing from Mr O’Malley, who reaches the end of his two-term limit next year, and, from the Obamas and Clintons.
Elsewhere, former US ambassador to Ireland Tom Foley, a Republican, ran a competitive contest in the race to be governor of Connecticut, a blue state, but he was beaten by Democratic incumbent Dannel Malloy by 51 per cent to 48 per cent.
Mr Foley, ambassador in Dublin from 2006 to 2009, competed in a rematch of the 2010 election against Mr Malloy in a bitter race.
Irish-American Democrat Aimee Belgard, another first- time candidate for the House, was unable to beat her Republican rival in New Jersey.