Vocal Event of the Year at the ACM Awards is an annual showcase of some of the best collaborations in country music, often those including stars from other genres. This year, however, the ACM nominations for Vocal Event of the Year are keeping it all country.

"Craving You" is the upbeat, powerhouse duet from Thomas Rhett and Maren Morris; the pair made a stellar music video for the song, and audiences ate it up in 2017. But Morris is also in the running in this category with "Dear Hate," a collaboration with the legendary Vince Gill that was in 2016 but only released after the Route 91 Harvest Festival Shooting in October. It's a powerful message delivered by an equally powerful duo.

"Funny (How Times Slips Away)" comes from the late Glen Campbell's final album, Adios. It's a cover of a song that Campbell's longtime friend Willie Nelson recorded years ago, and their newly recorded duet version already scored the pair a win for Musical Event of the Year at the 2017 CMA Awards.

Chances are good that Keith Urban knew he had a mega-hit on his hands when he asked Carrie Underwood to join him for "The Fighter," another of this year's ACM Vocal Event of the Year nominees. Kane Brown, too, may have known that when he enlisted the help of his middle school pal Lauren Alaina on "What Ifs," a duet that spent most of 2017 climbing the charts to No. 1.

Who deserves Vocal Event of the Year at the 2018 ACM Awards? Vote for your pick in the poll below; you can vote as often as once per hour through the end of the day on Thursday, April 12. The Boot's staff will tally the votes and use them for our readers vs. staff predictions before the show.

The 2018 ACM Awards are set to take place in Las Vegas, Nev., on April 15, and air live on CBS beginning at 8PM ET. The ceremony will take place at the MGM Grand Garden Arena.

The Boot will be staying up late covering the most buzzed-about winners, fashion and moments at the 2018 ACM Awards. Readers can watch along with us by checking back to TheBoot.com for the latest ACMs headlines, liking The Boot on Facebook and following The Boot on Twitter.

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