Both women claimed four individual nominations and are also challengers in the favorite female artist pop/rock category, which is rounded out with Katy Perry and Kelly Clarkson.
Rihanna and Perry are also nominated for artist of the year, competing with Justin Bieber, Drake and Maroon 5. The award went home with Taylor Swift last year.See a full list of 2012 American Music Awards nominees
A new electronic dance music category has been added to the show and is up for grabs by David Guetta, Calvin Harris and Skrillex. Undoubtedly missing from the category were notorious party rockers LMFAO. The duo announced their hiatus late last month.
The 40th Anniversary American Music Awards will air on ABC7 Sunday, Nov. 18, and will feature a performance from Aguilera. Winners will be determined by online voting, which opened to fans Tuesday. Anyone wishing to cast their votes can visit the AMA voting website.