Mitt Romney's wife, Ann, has been called his "secret weapon," and she has taken aim at his stiff and aloof image.
Wearing a red dress and standing in front of photographs of her family, she received extended applause at the party convention that on Tuesday nominated her husband to face President Barack Obama in November.
Saying she wanted to talk to the crowd not about politics, but about "love," she related the early days of their courtship as well as the hardships, including her battle with multiple sclerosis.
"I read somewhere that Mitt and I have a 'storybook marriage.' Well, in the story books I read, there were never long, long, rainy winter afternoons in a house with five boys screaming at once.
And those story books never seemed to have chapters called MS or breast cancer," she said.
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"A storybook marriage? No, not at all. What Mitt Romney and I have is a real marriage."
Pollster Gallup said 42 per cent of Americans have a favourable opinion of Ann Romney, while her husband lags behind Obama in "likeability".
Romney's campaign has largely focused on the economy and his business skills, but Tuesday's effort painted him in a more human light that critics have said has been lacking so far.
Delegate Alice Butler-Short of Fairfax, Virginia, said she thought his image problem was unfair, but that Ann Romney's speech would portray him positively to less-engaged voters. "She is so sincere and so down to earth," she said after the speech.
"Everything she said was absolutely from the heart." It remained to be seen what reception the remarks would have among undecided voters, including the women Ann Romney addressed directly in her remarks. "we're not dumb enough to accept that there aren't better answers," she said of women who have been hard hit by the faltering US economy.
"And that is where this boy I met at a high school dance comes in. His name is Mitt Romney and you really should get to know him."
The speech received high praise from television commentators, but Democratic observerss continued to point to Romney's wealth as distancing him from middle-class voters. Ann Romney took on some of those critics with a smile.
She spoke of the humble roots of their parents, despite Romney's youth as the son of a car company executive and Michigan governor, and described university life when they subsisted on "pasta and tuna fish".
"But those were the best days," she said of the start of their 42-year marriage.
"Now we have five sons and 18 grandchildren. And I'm still in love with that boy I met at a high school dance."
Ann Romney described the early days at Bain Capital, not the takeovers that Democrats have said cost many workers their jobs, and pointed to his unheralded charitable works.
"It's true that Mitt has been successful at each new challenge he has taken on. It amazes me to see his history of success actually being attacked," she said.
"As his partner on this amazing journey, I can tell you Mitt Romney was not handed success.
He built it." Judging by the applause from the thousands of Republicans at the Tampa convention, she has at least convinced the party faithful of Mitt Romney's personal side.
Romney himself made an unscheduled appearance with his wife on stage, welling up with emotion as the song My Girl played. He smiled and waved before walking off arm-in-arm with his wife, and though he didn't say a word the message was loud and clear.
