The actress, who plays long-suffering political wife Alicia Florrick on CBS's The Good Wife, says she finds depicting the staid character a stretch.
"It's a challenge because she's so far from who I am," Margulies, 44, says in the January issue of Harper's Bazaar, on sale Dec. 21. "I'm not saying I'm a crazy sexual person, but she's such a repressed Wasp."
In her own marriage, Margules says, feeling "sexy" is vital. When asked what makes her feel sexy, the answer is her husband, lawyer Keith Lieberthal, whom she wed in 2007.
"I feel sexy when I'm happy," Margulies says. "If I'm going out on a date with my husband, I want to feel sexy. I want him to see me that way. So I think you have to make an effort. When you're in love, you feel sexy."
The actress, 44, posed for a racy "bad wife" photo shoot for the magazine and submitted to the cheeky questioning of her Scottish cast mate Alan Cumming, who writes that the duo has "a ball doing scenes together."
Margulies also says her resistance to marriage in the past was probably due to fear.
"It's not that I didn't want to get married as much as I didn't feel like I was the marrying type," Margulies says. "I saw myself as someone who would always have a partner, but I never liked the feeling of what marriage said. Looking back, I think I was just mostly scared of it. Strangely, when the time was right, it all seemed to make sense."
She shares with Cumming, too, that no matter how much success she finds, being a mom to son Kieran, almost 3, isn't easy.
“It's tricky being a working mom," she says. "You feel guilt all the way around. You want to be there for your husband, be there for your kids, be great at your job, all that stuff. But at the end of the day, if you put everyone in front of you, what happens to you?”
For more photos and a behind-the-scenes video from the shoot, go to www.harpersbazaar.com/margulies.