'X Factor' Finale Recap: The Underdogs Vs. The Front-Runners

x factor finale carly rose sonenclar P
Ray Mickshaw / FOX

After a very long three months of glitter explosions, confetti cannons, spiky outfits, leopard spots, "Fifth Unison" jokes, endless sniping among the judges and the many faces of Britney Spears, The X Factor finale finally arrived Wednesday night.

Opening with a touching number honoring the victims of the Sandy Hook Elementary School shooting, featuring many of the top 16 performers, the show acknowledged the Friday tragedy in a fitting tribute before resuming its mission to find a $5 million winner.

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“It's a schoolgirl against a family man against five girls who have never given up," summed up co-host Khloe Kardashian.

For their big finish, the last three standing -- Carly Rose Sonenclar, Tate Stevens and Fifth Harmony -- had just three songs apiece to perform in front of the X Factor judges and America. Each finalist, it was announced, would repeat one song from the season, duet with a celebrity vocalist and perform a selection that would leave a “lasting impression.”

For extra effect, live feeds were set up in the final acts' hometowns complete with cheering fans, camera-stunned mayors and even more confetti. In Westchester, N.Y., they're holding up signs for Sonenclar, screaming, jumping and even declaring the day “Carly Rose Sonenclar Day.” Not to be outdone, Stevens was awarded the ultimate trophy -- a water tower in Belton, Mo. -- while the home base for Fifth Harmony was Ally’s stomping grounds of San Antonio, where a local pizza shop owner named a pie after them.

So who will be standing in the rainbow of confetti and awarded the $5 million recording contract Thursday? Truth be told, each act brought their A game, but one act really stepped it up and could pull a huge upset on Thursday night’s final episode featuring Pitbull and One Direction. Read on for a breakdown of the night's performances.

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Theme One: Song of the Season

Carly Rose Sonenclar

Song: “Feeling Good” by Nina Simone

Clad in leather pants and a hat fit for a New Year's Eve celebration, Sonenclar repeated her audition song, which Simon Cowell said “blew him away” the first time he heard it. While all three judges were in agreement that Sonenclar nailed her first song, it didn’t have quite the same impact as her audition. But the ever-so-theatrical Sonenclar did hit some glory notes, jazzing up the arrangement and showcasing her pipes on an a cappella opening. L.A. Reid was impressed, telling Sonenclar that she topped everything she did this season. Demi Lovato told the 13-year-old she would “inspire so many young girls to follow their dreams.” “I think it's so cool to see somebody so young be able to command the stage,” she said, while Cowell  believed she “sang it better tonight” than in her audition. Mentor Spears was elated: “We’re going to win this!”

Tate Stevens

Song: “Anything Goes” by Randy Hauser

Stevens earned his ticket to the show with this song during his audition, and he might have topped that moment Wednesday night. The song is a perfect choice for Stevens, as it showcases his arena-ready vocals and good-guy persona. One question: Was anyone else put off by the Christmas trees onstage? It seemed an odd choice (also, did you catch country music fan Mike “The Situation” Sorrentino of Jersey Shore in the crowd?). The judges loved it and praised his consistency throughout the competition. “When you go straight-down-the-middle country, you are right on.” Lovato, who claimed obsession with the country crooner, called it a “stadium performance,” while Cowell said he was “made in America.” He congratulated the “unlikely pairing” of Stevens and Reid, who called his mentee, “lovable.” Stevens’ hometown boss, projected onscreen via satellite, said it best when he was asked whether the crooner should go back to his old job: “Hell, NO!”

Fifth Harmony

“Anything Could Happen” by Ellie Goulding

If Fifth Harmony was the underdog last week, that certainly is not the case after what they did Wednesday night repeating this song from just seven days earlier (even the big bow and fantasy staging with a floating pegasus returned). This was a tour de force that framed the girls as the pop girl group of the future. Not only did they harmonize, but they gave a show worthy of five Katy Perrys, natch. Reid was blown away, saying that he was completely shocked, didn’t believe they met on X Factor (sort of like a certain boy band from the British show?) and it was “magical.” Spears called them “spectacular, girly and fun.” Lovato said she hoped America would vote for them, and Cowell said he likes “being the underdog.”

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Theme Two: Song Duet With Surprises

Carly Rose Sonenclar

Song: “How Do I Live” with LeAnn Rimes

This is a ballad that should have been a cakewalk for Sonenclar, but something about the arrangement and Rimes' vocals didn’t quite jell. The weird thing is, it came off as one of those battle rounds on The Voice, with Rimes in the weird position of being outsung on her own song. (That might be unfair, as Rimes was hoarse because she was sick. But still.) Did the show torpedo the front-runner with this decision? The fact that Rimes' image in America is badly tarnished doesn't help, but people should vote for Sonenclar, not Rimes (think of it like Dancing With the Stars -- the judges watch the star, not the pro dancer, if you will). Spears, however, called it “shockingly amazing.”

Tate Stevens

Song: “Pontoon” with Little Big Town

Stevens originally wanted to duet with his hero, Garth Brooks, but that wasn’t possible, so he got to duet with the lovely ladies of Little Big Town. While this might appeal to die-hard country fans, it might not have done much to broaden Stevens’ base, and he looked like the odd-man out during the number (albeit, a very happy odd-man out). Reid wasn’t worried, however, telling Stevens how “comfortable” he looked onstage.

Fifth Harmony

“Give Your Heart a Break” with Demi Lovato

With Lovato out of contestants, the show gave her something to do Wednesday night: sing with the group she loved to criticize early on but warmed up to when they knocked two of her hits out of the park in performance. This was no exception. The group, particularly Ally and Camilla, looked so at home with the superstar judge, and Cowell invited Lovato to join as a sixth member of the group. No more Fifth Unison jokes. Host Mario Lopez, in one of his best quips of the season, renamed them, “Sixth Harmony.”

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Theme Three: Last Impression

Carly Rose Sonenclar

Song: “Hallelujah” by Leonard Cohen

Sonenclar did a terrific job on a song done to death on just about every reality show (remember American Idol’s Jason Castro’s version?), including The Voice, which covered it this week in a beautiful tribute to the shooting victims of the Sandy Hook Elementary School. Sonenclar, backed by a full choir, looked beautiful and, yes, “angelic” on the number and couldn’t have possibly done any more to leave a solid lasting impression on the audience. Was it enough? "You've had a good night," Cowell said. Spears felt extremely confident: "I feel like that song alone is worth $5 million, so get out your checkbook, Simon.”

Tate Stevens

Song: “Tomorrow" by Chris Young

Stevens' final bow on The X Factor stage found him in familiar territory, belting out yet another country staple firmly in his wheelhouse. Lovato got a little misty knowing this is his last performance, but it’s impossible not to envision Stevens at next year’s Country Music Awards. As Cowell noted, we'll likely be hearing about the Belton (soon-to-be Nashville) resident's record sales next year. Reid, who recalled earlier that he had a “tantrum” when he first learned of his assignment to the Over 25s category, looked satisfied. “You had a really good night,” said Cowell.

Fifth Harmony

Song: “Let It Be” by The Beatles.

This was a strange decision because Emblem3 was eliminated after doing a Beatles song, but the girls sang it well, with each’s vocal characteristics getting a chance to shine. This is important because in many groups, two or three singers get to do the heavy lifting, and in this choice the public got to hear each individual girl. Was it the right move? Reid told them they were like “magic happening before our eyes,” and Cowell had nothing but pride for his girls. “You're five great singers, and it's really important to remember that," he said.

So who deserves the crown? We have to give the edge to Fifth Harmony for coming out fighting, while Sonenclar and Stevens seem destined for strong careers no matter what the vote. Who do you think will win Thursday? Let us know in the comments below.

Twitter: Michele Amabile