Brad Paisley leads all finalists for the Academy of Country Music Awards with six nominations, but the biggest surprise might be former Trick Pony singer Heidi Newfield's five nods.

Paisley was nominated Wednesday for entertainer of the year and male vocalist, an honor he won last year. He's also a finalist for record, song and video of the year for "Waitin' on a Woman," and for vocal event of the year for "Start a Band" with Keith Urban.

Newfield released her solo debut, "What Am I Waiting For," last August after 10 years with Trick Pony. She's nominated in five categories, including song of the year and video of the year for "Johnny & June," an ode to the late Johnny and June Carter Cash.

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The Academy of Country Music Awards air on CBS from Las Vegas on April 5.

Kenny Chesney, the ACM's entertainer of the year four years running, received four nominations, including another in the coveted entertainer category. A fifth straight win would tie him with Alabama for the most consecutive entertainer trophies.

George Strait and Jamey Johnson also received four nominations apiece. Johnson, a relative newcomer, is up for top new male vocalist, as well as single record of the year and song of the year for his hit "In Color." This is the first time Johnson has been nominated as an artist. He won song of the year honors in 2006 for co-writing Strait's "Give It Away."

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Strait is again in the running for song of the year, this time for "I Saw God Today." The superstar's other nominations are for entertainer, top male vocalist and video of the year.

For the first time in her career, Carrie Underwood is nominated for entertainer of the year. Historically, women don't get nominated too often in this category. If she wins, she would become the just the seventh female to take the award, putting her alongside Loretta Lynn, Reba McEntire and, most recently, the Dixie Chicks in 2000.

Underwood is also up for female vocalist, which she's won the last two years.

Urban got three nominations: entertainer of the year, top male vocalist and vocal event of the year for "Start a Band."

Trace Adkins, Brooks & Dunn, Little Big Town, James Otto, Jake Owen, Taylor Swift and Sugarland each received two nominations.

Several categories will be opened up to interactive fan voting, including entertainer of the year for the second time. Last year's winner, Chesney, took issue with allowing fans to choose the show's top honor instead of ACM members, saying the method amounted to "complete disrespect" of the artists because it turned the award "into a sweepstakes to see who can push people's buttons the hardest on the Internet."

Online voting will begin Friday on GACTV.com.

Jessica Simpson, LeAnn Rimes, Kellie Pickler and Julianne Hough read the nominations live Wednesday during CBS' The Early Show broadcast.

"Dancing with the Stars" champ Hough is nominated for top new female vocalist, an honor she says caps "an amazing year and a half" in which she's toured with Paisley and Strait and had a hit song with "That Song in My Head."

"I've definitely very fortunate," she said. "Everybody has been so welcoming."

Rimes will receive the ACM/Home Depot Humanitarian Award for her community service and charitable giving.