Senator Clinton may have drawn rousing ovations during her appearances at civil rights rallies in Selma, Ala., on Sunday, but it was not what she said that stirred the most buzz yesterday — it was how she said it. A 27-second snippet of audio clips that made its way around political Web logs showed New York’s Illinois-born senator adopting a Southern drawl during parts of her speech at a Selma church. The accent was most pronounced during Mrs. Clinton’s recitation of a hymn and on words such as “afternoon.” The clip was posted on the Web site ifilm.com with the title “Kentucky Fried Hillary.” A link to it led the popular Drudge Report for much of the afternoon. The Clinton campaign declined comment last night. Mrs. Clinton, who has a history in the South as a former first lady of Arkansas, has slipped into a Southern accent before — she dropped an occasional “y’all” into speeches in South Carolina last month. But she is far from the only politician whose voice may change for the audience. Videos also showed Senator Obama of Illinois adopting a less pronounced Southern accent on Sunday in Alabama.