Dan + Shay are up for Vocal Duo of the Year at Sunday (April 19)'s 2015 ACM Awards, and after being nominated in 2014 as well, the duo says that it's kind of surreal to have been nominated twice in the short time they've been working together.

"Being nominated was the craziest thing ever. Just being nominated is such an honor for us," Shay Mooney tells The Boot. "I mean ... this is our second time being nominated, and I think it’s crazy, just for the amount of time that we've been together as a duo, it’s just crazy that we got nominated and this is our second year.

"It’s kind of ridiculous to us; we’re so honored and everything that we’re even nominated," he adds. "To win would be awesome, but just to be there for free is pretty cool.”

The pair jokes that they've tried to sneak into the awards show without an invitation in the past, but despite the fact that they're nominees, they still get super-excited seeing some of the other artists at the ceremony.

“We fanboy out seeing all the artists, like Keith Urban and all those guys," Dan Smyers says. "We walk by them, and we’re like, 'Should we get their autograph?’”

Dan + Shay will also be hitting the stage during Sunday's show, to perform with Nick Jonas, whom they've only met once before, while in New York for the Macy's Thanksgiving Day Parade. (Fun fact: Dan + Shay's tour opener Canaan Smith covered Jonas' song "Jealous" at a recent tour stop.) Smyers and Mooney are keeping mum on what songs they'll be performing, but they did say that it will be a mashup -- and that Smyers has been working on the track.

“To be performing is kind of next-level," Mooney says. "It’s going to be really cool, man. Dan’s been working really hard on the track, and it sounds bangin’, so it’s going to be a really fun performance."

After the ACMs, the duo will return to the road to finish up their 2015 Where It All Began Tour, which runs through April 25. They released their newest single, "Nothin' Like You," earlier this year.

The 2015 ACM Awards will air live from AT&T Stadium in Arlington, Texas, on April 19 at 8PM ET on CBS.

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