Strong show from 'Mom-in-Chief'

First ladies don't hold debates. Instead, the wives of presidential candidates give competing convention speeches. Michelle Obama last night said she loved Barack Obama more now than she did four years ago because he hadn't changed since the days when his proudest possession was a coffee table he found in a Dumpster.

"We were so young, so in love and so in debt," she said.

Last week, Ann Romney had a similar description of early wedded bliss to Mitt Romney, reminiscing about their start in a basement apartment eating pasta and tuna fish dinners on an ironing board: "We were very young. Both still in college. There were many reasons to delay marriage, and you know? We just didn't care."

Michelle Obama's speech wasn't just a touching testimonial to her husband; it was a vivid, live-on-network-television reminder of how little the role of first lady has changed. At a time when powerful career women are showcased at each convention - former secretaries of state, senators, governors, activists - the role of the president's wife - or an aspiring president's wife - seems pretty much frozen in the template set by Jacqueline Kennedy and Pat Nixon.

It's hard to find two women farther apart in background, education and ideology than Michelle Obama and Ann Romney, yet their convention personas are remarkably similar. They are warm, caring and, most of all, irreproachable helpmates.

Like Ann Romney before her, Michelle Obama was tapped to draw a personal, approachable portrait of a husband who is sometimes seen as aloof and didactic. Both women spoke winningly, but Michelle Obama, who had addressed a political convention before, gave the strongest performance.

Naturally, there was no overt hostility between the two sides. Michelle Obama never uttered the word "Romney." Earlier, when Ryan Seacrest asked her to assess Ann Romney's speech, Michelle Obama said, "I didn't watch it." Yet last night she managed to draw a contrast between the two candidates, elliptically.

Michelle Obama said she loved that after law school, her husband turned down "high-paying jobs" to help people find work in poor communities. "Because for Barack," she said, "success isn't about how much money you make. It's about the difference you make in people's lives."

Ann Romney said she admired her husband's drive and business acumen. "And let's be honest," she told Republicans in Tampa, Florida. "If the last four years had been more successful, do we really think there would be this attack on Mitt Romney's success?"