Ann melted American hearts, but has she changed the game?

By universal consent, she was fabulous. In her crucial speech to the Republican delegates and all America, Ann Romney came across as warm, affectionate, engaged, and – above all – normal. She even managed to sound spontaneous, although modern political conventions are scripted to the nanosecond.

If anything, she was too good. "Ann Romney is so gifted at politics," wrote the TV critic of The New York Times, "she may actually make her husband look a little bad."

The Boston Globe, another paper not noted for its sympathy for things Republican, hailed her performance as "the best convention speech by any candidate's spouse – and certainly the most important".

The question is, will she make a difference? Many convention speeches have been hailed as sensations, but scarcely endure a news cycle. There have been exceptions – such as Barack Obama's unforgettable keynote at the Democratic convention of 2004. Whether Ms Romney has changed the game will be apparent in two stages. The first will be in her husband's poll numbers – whether her loving tribute to him will make him more real and accessible. The second will be evident on election day: whether Mitt Romney can win back some of the women voters who currently prefer Mr Obama by 20 per cent or more.

In her speech, as cheering delegates waved placards proclaiming "We love Ann" and "Women for Romney", she pressed all the right buttons. She spoke directly but not cloyingly about her miscarriages, the breast cancer she has overcome and the multiple sclerosis she fights to control.

Women were especially affected by the country's economic problems – and Ms Romney, despite her wealth and privilege, made clear she was a member of the club. "If you listen carefully, you'll hear the women sighing a little bit more than the men," she said. "It's how it is, isn't it?" Mothers always had to work that little bit harder to keep things going. "It's the moms of this nation – single, married, widowed – who really hold this country together."

But there were limits to the effusiveness. She produced no humorous, mildly indiscreet anecdote that would have helped "humanise" her husband. Nor did she say a word about abortion, let alone seek to soften the Republican party's uncompromisingly hostile stance on the issue which makes many women reluctant to support it.