That is the analysis of Ulster-Scots historian and commentator Gordon Lucy, after the outgoing US president delivered his final address as American commander-in-chief to the Democratic National Convention during the week.
Mr Lucy said that the president’s decision to explicitly make reference to that part of his heritage was a “highly-intelligent” manoeuvre, designed to draw on the “immense political clout” of voters who also have Protestant Irish ancestors.
Mr Obama had delivered his speech on Wednesday in Philadelphia, exactly 12 years after he first gave an address to delegates at the conference.
In his 2004 speech, Mr Obama had spoken of his father’s African background, plus his mother’s US-born family. In his 2016 speech, he harked back to that speech, dwelling particularly on his mother’s Kansas-based side of the family.
In a transcript of the speech provided by Newsweek online magazine, he said: “See, my grandparents, they came from the heartland.
“Their ancestors began settling there about 200 years ago... They were Scotch-Irish mostly – farmers, teachers, ranch hands, pharmacists, oil rig workers.
“Hardy, small-town folk. Some were Democrats, but a lot of them, maybe even most of them, were Republicans. Party of Lincoln.”
Reviewing his speech, Mr Lucy – a member of the Ulster-Scots Community Network, said: “President Obama is deliberately trying to tap into the ‘Scotch-Irish constituency’ which may well prove critical to Mrs Clinton’s prospects of winning in November.
“It is worth pointing out that the ‘Scotch-Irish vote’ is more a cultural mindset, than a strictly ethnic vote.
“The novelist Tom Wolfe – a Virginian with Ulster-Scots ancestry – credited the ‘Scotch-Irish’ with winning the very tight Presidential election of 2004 for George W Bush.
“We may be looking at a re-run of that election in 2016 and on this occasion the ‘Scotch-Irish vote’ is most likely to favour Trump over Clinton...
“Thus President Obama is endeavouring to embrace the ‘Scotch-Irish constituency’ – and it is a highly-intelligent political calculation – by openly endorsing what might be fairly called the ‘Webb thesis.’”
He explained that the “Webb Thesis” refers to James Webb, ex-Democratic senator for Virginia, who “forcefully contended that the Scots-Irish have played a central role in American history and culture”.
He added: “He credits them with a culture that shaped the emotional fabric of the nation, that defined America’s unique form of populist democracy, created a distinctively American musical style, and through the power of its insistence on personal honour and adamant individualism, has become the definition of ‘American’ that others gravitate toward.
“This is what gives the Scotch-Irish vote its immense electoral clout.”
• British Isles links of top politicians:
Mr Obama’s links to Ireland have been well-documented.
In 2011 he paid a visit to the Co Offaly town of Moneygall, where some of his ancestors hailed from. TheTelegraph of London, among other sources, has stated that Church of Ireland Canon Stephen Neil, based near Moneygall, had found references to his ancestors in the parish records.
In a 2007 article, the paper said: “The presidential candidate, the son of a Kenyan goatherd, comes from an Irish Anglican family, many of whom emigrated to the New World at the time of Ireland’s potato famine in the 1840s.”
US presidential contender Donald Trump is part-Scottish, his mother having been born on the Isle of Lewis, while Hillary Clinton’s heritage is reported to be Welsh in large part.