WHEN Ernesto Martinez, the lead costume designer for the new HBO series “Veep,” started to think about how to dress the show’s star, Julia Louis-Dreyfus, for her role as the country’s first female vice president, he quickly decided that inspiration would have to come from somewhere other than the current office holders in the nation’s capital.


“Most politicians, their stab at looking good is really not so great,” Mr. Martinez said in a recent phone interview from Los Angeles. Hillary Rodham Clinton’s much-chronicled pantsuits were never an option. “The idea was to be powerful, but attractive,” he said.


Even Nancy Pelosi, the California congresswoman known for her stylish power suits, was dismissed as a possible role model. Too old, Mr. Martinez thought, for Ms. Louis-Dreyfus’s character, Selina Meyer. (Though he did incorporate into the character’s wardrobe some “statement” jewelry, similar to that often worn by Ms. Pelosi.)


“Selina Meyer is a really beautiful woman,” Mr. Martinez said, adding that he had to find outfits that would accentuate the character’s looks without diminishing her credibility as vice president.


Even research on other TV shows that have featured strong female characters, like “The West Wing” and “The Good Wife,” failed to yield a look that Mr. Martinez felt would be right for “Veep.” “I liked the way the men looked, but there was nothing like Selina Meyer,” he said.


Mr. Martinez, a veteran Hollywood costume designer, didn’t have much to draw on from his past work. He has worked on series like the original “Beverly Hills, 90210” and “Eastbound & Down,” but for no characters who were female politicians. He did dress Richard Riordan, during his successful campaign for mayor of Los Angeles years ago. “Riordan was a very wealthy man, but he was just not into his clothes,” Mr. Martinez said. “He was a really sloppy guy who wore threadbare shirts, so I had to do a total makeover.”


In the end, Mr. Martinez found a role model in Washington — but not one who holds elective office: Michelle Obama.


“Michelle Obama is the best thing that Washington, D.C., has seen in a long time,” he said, speaking of her well-documented love of fashion and the wide range of designers she has favored over the last three years. “It’s a whole new era at the White House now — it’ll probably be never like that again — and we wanted to make it current. Plus, Julia loves Michelle Obama.”


Like the first lady, Ms. Louis-Dreyfus flaunts a lot of bare arm in “Veep” and rarely wears black. “Color works well on Julia — burgundy and earth tones made her friendly,” the costume designer said.


Then there’s the assortment of high-fashion designer labels. The fitted dresses are mostly by Christian Dior and the suits by Prada. For all-American measure, Mr. Martinez also used daywear by Tahari. As for the occasional va-va-voom piece, he said that it came about almost by accident. “The clothes were actually semi-fitted,” he explained. “They were not supposed to be sexy, just tailored, but it turns out Julia has quite the body. She’s naturally sexy, so it came off that way.”


Kate Betts, a former editor at Vogue and Harper’s Bazaar and the author of “Everyday Icon: Michelle Obama and the Power of Style,” said she isn’t surprised that Mr. Martinez turned to the first lady for sartorial inspiration. “Michelle Obama is our first post-feminist first lady,” Ms. Betts said. “She has academic credentials just as good as her husband’s. We can imagine a first lady as a vice president now. We can imagine a female president.”


Interestingly, two highly prominent female politicians were initially discarded as role models — “Julia actually said in the beginning that she didn’t want to look like Sarah Palin or Michele Bachmann,” Mr. Martinez said with a laugh — but then their style became integrated into the show’s look. “We did do a couple things,” Mr. Martinez said. “There was a spot on ‘Meet the Press’ that channeled Bachmann, and then there was a spin on Sarah Palin for a TV interview.”