MICHELLE Obama dazzled Dublin with her grace and charm, and almost outshone her husband in Belfast with her eloquence, sounding every inch the professional politician. And that is exactly what could be on the cards for her.
The talk in Washington is that she is a politician-in-waiting with her eyes on a particular seat.
"She (Michelle) is only waiting for the right time," a Washington political insider told me. And 2016 would fit that bill.
By then, her husband will be ending his second term and she would have no campaigning constraints. And 2016 also happens to be the year that a US Senate seat will be up for grabs in her native state of Illinois.
She would be a fundraising magnet with the power of the Obama political machine behind her. A poll has even been carried out on her chances in a hypothetical match-up against Mr Kirk. It had her leading 51pc to 40pc.
She would be a formidable candidate. A lawyer and an intellectual powerhouse, who excelled at Princeton and Harvard Law School, she first met her husband when she mentored him at a Chicago law firm.
She lacks political experience. But so did another first lady before she went on to become a US senator for New York.
Chicago is also the Obama political power base and it has a strong African-American electorate. Mrs Obama would also do well among Irish-American voters. Like the Clintons before them, the Obamas understand that the Irish vote matters and they have been good at wooing the Irish.
Bringing the girls here is part of that. The visits are not sentimental sideshows. They happen because they yield results.
But it's a two-way street. When the president of the United States comes here and tells the world "this island is chic", it is the kind of publicity about which tourism chiefs can only dream.
If Mrs Obama does decide to run against Mr Kirk, the race would be by no means an easy one.
He has won much sympathy and admiration for his courage in returning to the Senate after suffering a stroke.
But if she were to fight and lose a race against Mr Kirk, that would not be the end of the story. Only the timing would change. The senior Democratic senator from Illinois, Dick Durbin, will probably be ready to retire either in 2016 or 2020.
As we saw in Ireland, Mrs Obama would be a powerful campaigner. She can work a crowd and make a rousing speech as deftly as her husband. She is, in many ways, already perfecting her political stump speech. Her demeanour and her words in Belfast were evidence of that.
Indeed, perhaps Belfast could be the place where history began to repeat itself for two US first ladies. Like Mrs Obama this week, Mrs Clinton made a huge impression there in 1995 with her husband.
Some question whether Mrs Obama would be up to the rough and tumble of US politics. Certainly there have been some mis-steps. She raised eyebrows recently when she threatened to walk out of a fundraiser when she was heckled.
Then she got into hot water two weeks ago after a perceived snub to China's first lady by not attending a meeting in California that Mr Obama was having with President Xi Jinping and his wife Peng Liyuan. Mrs Obama said she needed to be in Washington as her daughters finished up the school year.
She is saying little of her plans. She has said she wouldn't run for office because she lacks the patience. But Mrs Clinton similarly deflected questions before her Senate run.
Mrs Obama will have to make up her mind by December 2015, the deadline for filing entry papers for the Illinois race.
So 2016 could be a fascinating year in US politics, with one first lady possibly battling for a US Senate seat and a former first lady battling for the US presidency.