The wife of South Korea's main conservative party candidate has taken a leading role ahead of next week's elections, campaigning on her own to tarnish the image of the liberal front-runner and his spouse and turbocharge her husband's bid.

Last week, Seol Nan-young even took her unusually vocal criticism onto Saturday Night Live Korea, joking about scandals dogging the wife of her husband's chief rival and promoting a clean family image for her spouse, conservative People Power Party candidate Kim Moon-soo.

Kim is fighting an uphill battle to separate himself from former President Yoon Suk Yeol, who was impeached and removed from office over a short-lived martial law attempt in December.