Her critics point to an empty, wind-swept Belfast park - which Clinton a decade ago proclaimed would become Northern Ireland's first Catholic-Protestant playground - as evidence that her contribution as peacemaker was more symbolic than substantive.
"She was in charge of christening this wee corner (of the park) as some kind of peace playground. It never made any sense then, and there's nothing there today," said Brian Feeney, a Belfast political analyst, author and teacher. "Everything she did was for the optics."
Critics say the playground-that-never-was illustrates the wider lack of accomplishment from Clinton's half-dozen visits to Northern Ireland - that they emphasized speechmaking, chiefly to women's groups, leaving no lasting mark.
Clinton twice addressed audiences of schoolchildren at Belfast's Musgrave Park, in September 1998 and May 1999. She declared that Protestant and Catholic youths must learn to play together but needed a safe place to do it - and helped plant a tree on the spot where a special cross-community playground would be created. Belfast did have other parks.
Nearly a decade later, Musgrave Park remains as it was: a well-groomed, rather lonely place sandwiched between a hospital and a highway, where adults jog and walk their dogs amid birdsong and spring flowers. The Belfast group touting the "Play for Peace Fund" silently shelved the idea within months although Clinton often referred to the project as an inspiration to a divided world.
Clinton and her campaign aides say her championship of a greater role in the peace process for women on both sides in Northern Ireland's conservative, male-dominated politics made a substantial contribution to the result.
"Women ... were persistent in the process ... (Clinton) came back to Ireland time and time again to be with them, to hear them out, to hear about the progress they were making," said Melanne Verveer, a Clinton aide who now works on the campaign.
That's a view supported by the recollections of some U.S. officials involved in the peace process at the time.
Former Democratic Sen. George Mitchell, who brokered the peace accord, recalled Clinton as having "a sustained interest over a long period of time" in Northern Ireland's troubles and that she "became very knowledgeable about the issues and the participants." ()
"By virtue of her position, her stature, I think she made a real contribution to encouraging and supporting that phase of the process and the entire process itself," said Mitchell, who has remained neutral in the drawn-out struggle between Clinton and Illinois Sen.for the Democratic nomination.
Clinton has described herself as a catalyst for bringing Catholics and Protestants together, even though these activists regularly were meeting each other at many forums by the mid-1990s.
In 1997 she delivered a speech to the University of Ulster that was supposed to inaugurate an annual lecture series honoring a Belfast peace activist, the late Joyce McCartan, whom Clinton briefly met in 1995 during her husband's first of three whirlwind tours of Northern Ireland. The university hosted one more such speech, in 2000, none since.
A political party established in 1996 to promote women in politics, the Northern Ireland Women's Coalition, drew inspiration from Hillary Clinton's words and example. Voters weren't as convinced; the party folded in 2006 after all its candidates lost in two straight elections.
"It's crazy for Hillary to say she played a role in bringing peace to Northern Ireland. ... She seems to be confusing her record with her husband's," said Robin Wilson, founder of a Northern Ireland think tank, Democratic Dialogue.
In a December 2007 interview with ABC News, Clinton said: "In just the last few weeks, the new leaders of the Northern Ireland government, Dr. Ian Paisley and Martin McGuinness, made a special effort to see me. Why? Because I helped in that process, not just standing by and witnessing, but actually getting my hands into it, creating opportunities for people on both sides of the sectarian divide to come together."
Clinton's longtime claims to have played a difference-making role in Northern Ireland attracted no criticism until the buildup to St. Patrick's Day this year. To some ears, her most recent comments have raised a false impression that she helped produce the landmark Good Friday peace accord of 1998.
Irish Prime Minister Bertie Ahern came to Clinton's defense, meeting with the senator in Washington - and making his first phone call to Obama.
"I think for anyone to try to question the Clintons' huge support (for Ireland) and start trying to nitpick and saying, 'But she wasn't sitting down at the negotiation table' - sure, we know she wasn't sitting down at the negotiation table," Ahern said.
After suffering criticism from rival Obama's campaign and Protestant politicians in Northern Ireland, Clinton this month backed off language that suggested she was ever involved in the 22 months of negotiations that preceded the Good Friday pact.
But Clinton still suggests that she wielded a hidden hand over the diplomatic triumph.
"I wasn't sitting at the negotiating table, but the role I played was instrumental," she said in a March 13 interview with National Public Radio.
Clinton's campaign has distributed statements backing up her claim from Nobel laureate John Hume, the Catholic intellectual heavyweight of the peace process, who credited her with making "countless calls and contacts," and leaders of Sinn Fein, the party that former President Clinton helped to bring in from the diplomatic cold caused by Irish Republican Army violence.
In Northern Ireland, the endorsements from Hume, Sinn Fein and Ahern are broadly recognized as reflecting Irish Catholics' desire for maximum international sympathy, specifically from the U.S. The retired Hume, in particular, boosted his clout by carefully cultivating friendships with U.S. politicians, chiefly Democrats.
For them, a President Hillary Clinton offers the best chance of a return to the pro-Irish policies of her husband, who broke with decades of State Department deference to Britain, an approach resumed under President Bush.