Robyn is likely familiar with this song via the 1977 version by Dr. Hook, who also released "When You're In Love With a Beautiful Woman," which he also has played in his encores. From Wikipedia:

"Walk Right In" is a country blues song written by musician Gus Cannon and originally recorded by Cannon's Jug Stompers in 1929 by RCA Victor. In 1959, it was included on the compilation album The Country Blues. Another version of the song by the Rooftop Singers, with the writing credits allocated to group members Erik Darling and Bill Svanoe, became an international hit in 1963.