A week ago, pundits admired Ann Romney’s speech at the Republican National Convention. Faced with the task of humanizing her husband, she tried to show Mitt Romney’s other side. But Tuesday night, rather than attempting to change how Americans thought of President Obama, Michelle Obama doubled down on both the president’s personal strengths and his policies, in a superb speech that sets a very high bar for the rest of the Democratic National Convention.

Like Ann Romney’s speech, Michelle Obama’s was heavy on biography. But where Ann Romney only cited “long, long rainy winter afternoons in a house with five boys screaming at once” to illustrate her personal difficulties, Michelle Obama drew on her father’s struggles with multiple sclerosis, his determination to pay her college tuition, Barack’s childhood being raised by a poor single mother and a grandmother who “hit a glass ceiling,” and the couple’s struggles with student debt. Of course, Michelle Obama had more material to draw on than Ann Romney did, but without mentioning the latter or her husband by name, Michelle Obama thoroughly bested Ann Romney’s attempts to connect with voters.

But the First Lady wasn’t content merely to rely on personal stories; she also connected those stories to Obama’s policies. Alongside more dependable applause lines such as lowering taxes on the middle class, the first lady explicitly included more divisive issues such as the Affordable Care Act, the Lily Ledbetter Fair Pay Act, gay marriage, contraception, and even a defense of the president’s economic record. And she connected the personal tales to a succinct, eloquent summary of the Democratic Party’s central idea in this election:

Barack knows the American Dream because he’s lived it . . . and he wants everyone in this country to have that same opportunity, no matter who we are, or where we’re from, or what we look like, or who we love.

And he believes that when you’ve worked hard, and done well, and walked through that doorway of opportunity . . . you do not slam it shut behind you . . . you reach back, and you give other folks the same chances that helped you succeed.

To keep things in perspective, Michelle Obama’s speech probably won’t have much, if any, effect on undecided voters. But what a first lady’s speech can do is build momentum for the rest of the convention and fire up the party’s base, while not coming across as very partisan. Michelle Obama accomplished all of those tasks.

One final note: It’s worth watching Michelle Obama’s speech to get a sense of how much delivery matters. The words themselves were decent, but her delivery of them was essential to the speech’s success.

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