Nick Viall Might 'Be Left at the End' of 'The Bachelor,' Says Host Chris Harrison

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If Nick Viall does find love on The Bachelor, will it last?

Ahead of the 36-year-old reality star handing out the final rose, the ABC show's host Chris Harrison revealed on Good Morning Americathat this Bachelor finale might not have a happy ending. "[This] might be the first Bachelor in the history of this entire franchise to be left at the end," he admitted. "And believe me when I tell you, he knows that."

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GMA also aired a preview clip from the finale where Viall reveals that he's been "falling in love" with someone for a "very long time" -- but is he talking about Raven or Vanessa? "I feel like sometimes I've been fighting it, and I'm not fighting it any longer," Viall shares. "I am going to ask her to marry me, and my only fear now, is what if she says no?"

"If I leave here alone, I'll be devastated, I'll be heartbroken," he adds.

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Harrison thinks Viall has narrowed down his choices to "two incredible women" that "could not be more different."

"Different walks of life, different worlds, different accents, different everything," he explained. "But both check off boxes, to be so crass, of things that mean a lot to him."

Harrison also admitted that he's "stunned" that Vanessa -- a special education teacher in Montreal, Canada -- has "made it this far."

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"She is a brilliant woman," the host noted. "I think sometimes her brain just gets the best of her."

"What I find fascinating about this show, is the capacity for people to love more than one person at a time," Harrison continued. "We all have this capacity to do it, I just don't think we allow ourselves because it’s taboo."

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Bachelor fans are eager to see if Viall finally finds love on reality TV, and as for the Bachelor himself, he told ET that he's "thankful" to have the show behind him. "Chris [Soules] and Ben [Higgins] and some other people who had been leads who I talked to in the past certainly prepared me," Viall said. "I don’t think anyone can fully appreciate the challenges that come with it until they're a part of it…until you live it and until you experience it and until you feel it, it's something quite different."