Photo If t was a single moment that captured what would carry Hillary Clinton to the cusp of the 2016 Democratic nomination, it came not during her sun-splashed campaign kickoff in New York last June, or in any of her speeches celebrating hard-fought primary victories over Senator Bernie Sanders.

Mrs. Clinton’s steely fortitude in this campaign has plainly inspired older women, black voters and many others who see in her perseverance a kind of mirror to their own struggles.

Mrs. Clinton’s very durability – her tenacity, grit and capacity for enduring and overcoming adversity – could be exactly what is required to defeat Donald J. Trump.

“Even as first lady, it was ‘Who does she think she is?'” said Melanne Verveer, a close friend of Mrs. Clinton’s who was her White House chief of staff.

Mrs. Clinton’s confidants say it is only fitting that, having overcome so many obstacles before, including some of her own making, she now faces an opponent so eager to go negative with her – and to refight the bare-knuckled brawls that have defined her career.

Mrs. Clinton’s career has not taken a predictable route by any stretch.