Ms. Swift in Central Park with Harry Styles

And though relationships with the teenagers Harry Styles of One Direction and Conor Kennedy may have inspired ribbing that she is a cradle robber (along with providing even more song material), Ms. Swift, unlike Britney Spears at the same age, has mostly maintained an air of innocence until now.

“It’s Taylor’s back story,” said Janjay Sherman, the publicity and talent-relations director of Extra Extra, an events and marketing company that recommends celebrity pairings to corporate clients. “The whole ‘I was raised on a farm, I’m a country girl’ kind of thing was established before she crossed over to pop and mainstream,” Ms. Sherman added. “And with country, there’s a really clean wholesomeness that attaches to her.”

And controversy just might make her more interesting, particularly to high-end beauty and fashion companies. MAC Cosmetics, for one, doesn’t use marketing scores when selecting its outspoken celebrity collaborators, like Rihanna, whose first installment of her makeup collection with the brand has its debut this spring, said James Gager, senior vice president and creative director of the company, whose ambassadors have included hardly uncontroversial personalities like Lady Gaga and Nicki Minaj.

Designers are increasingly willing to lend Ms. Swift red-carpet gowns, said Alana Varel, a founder of Starworks Group, a company that pairs celebrities with clients like Miu Miu, Prada and Bulgari, including Kirsten Dunst, Rachel Weisz and Julianne Moore for the jeweler.

Ms. Swift has already registered approval among fashion commentators this year, particularly when in white, like the Grecian-style gown with metallic beaded straps by J. Mendel that she wore to the Grammy Awards in February, and a plunging Ralph Lauren cap-sleeved dress at the People’s Choice Awards in January.

“She’s hitting her stride in style,” Ms. Varel said.