Television's Mad Men will bid for a fourth straight Emmy on Sunday, hoping to fend off the Prohibition-era gangsters of Boardwalk Empire and the warring kings and knights of Game of Thrones for the industry's top honors.

After months of anticipation, the stars and creators of dozens of comedies and dramas gather in Los Angeles for the annual Prime-time Emmy Awards ceremony that celebrates the best of television.

More than 20 Emmys will be handed out on Sunday in a live telecast on the Fox network hosted by Glee star Jane Lynch, who could find herself accepting an acting award for her role as a sarcastic cheerleading coach on the hit musical comedy.

But all eyes will be on the top prizes -- for best comedy and drama series -- and some major upsets could be in store, especially in the acting categories.

ABC mockumentary and 2010 Emmy comedy series winner Modern Family goes into Sunday's awards with 17 nominations, including acting mentions for all six of its stars.

That puts it in a commanding position for a repeat victory over rivals Glee, The Office, Parks and Recreation and The Big Bang Theory.

The contest for best drama is much closer. HBO's lavish new show Boardwalk Empire, with 18 nominations, has already taken Golden Globe and Screen Actor's Guild trophies and is regarded as a major contender, despite the 19 nods to Mad Men, the 1960s advertising drama on AMC.

Medieval fantasy series Game of Thrones, which proved a surprise success for HBO, has an army of fans, while CBS lawyer show The Good Wife starring Julianna Margulies topped an Xfinity TV poll on Facebook as favorite drama. Dexter and Friday Night Lights make up the other drama contenders.

ACTORS & ACTRESSES

Margulies also is the front-runner for best dramatic actress, along with Elisabeth Moss, who plays the quiet but feisty young Peggy Olson of Mad Men.

It is such a great showcase for Moss. It is quite a contest. I think Margulies will win, but it is very close, said Tom O'Neil of awards website TheEnvelope.com.

Jon Hamm, who plays suave but enigmatic Don Draper in Mad Men, also is hoping to clinch his first Emmy this year.

Hamm is the lead star of this Emmy-anointed show who has never won. But he has got to watch out for Steve Buscemi on 'Boardwalk Empire,' said O'Neil.

The HBO miniseries Mildred Pierce has a leading 21 nominations and is expected to deliver an acting Emmy for its star, British actress Kate Winslet.

But surprises could be in store for Emmy newcomer Melissa McCarthy of comedy Mike & Molly, who also stole the show in the summer movie Bridesmaids.

She is an outstanding comedic actress. She was also so funny and winning in 'Bridesmaids' and I think audiences got her and she won new fans, said Todd Gold, managing editor of Xfinity TV.

The popular reality competition slot is also a cliffhanger. Victory may finally be at hand for America's most-watched show American Idol, but Dancing with the Stars or So You Think You Can Dance could waltz away with the Emmy.