Otunga -- who graduated from Harvard Law School and was known as "Punk" while on I LoveNew York -- proposed to the Oscar-winner with a Neil Lane diamond ring on Friday, Hudson's representative confirmed to People on Sunday.
The couple, who have been dating for less than a year, both are natives of Chicago. Prior to Otunga, Hudson had dated childhood acquaintance James Payton for eight years and been the subject of unconfirmed engagement rumors.
The engagement to Otunga becomes the latest accomplishment in a busy year for Hudson, who also celebrated her 27th birthday on Friday. After landing film-acting roles in Sex and the City and The Secret Lives of Bees, the Idol alum sang the national anthem during the final evening of the Democratic National Convention in Denver, CO.
Her debut album, titled "Jennifer Hudson," is also slated to be released on September 30.