Valtteri Bottas is now thought to be the sole candidate to replace the world champion, who walked away from the sport days after winning the world championship.
Merhi, who wants to continue racing single seaters despite moving into LMP2 with Manor last year, said that he would have loved the chance to move to Mercedes, even if it was a highly unlikely proposition.
"Of course," he told Spain's sports daily AS. "Among other reasons, because the only thing you would need to do to win the title would be to beat Hamilton.
"It's as if you tell me there's a place at McLaren and all I have to do is beat Alonso! I'd be delighted to be there, but beating those guys would be another story," Merhi added.
"Anyone at Mercedes just has to beat Hamilton and that's almost impossible," he said.
"Rosberg did it on his third try so he needed time to make everything perfect and more reliable. (Jenson) Button beat Hamilton in a very bad year for Lewis, but I think of the current grid only Alonso could beat him.
"Nico did it, and I'm not saying it was by chance but it's true that he had things in his favour," Merhi added.
Bahrain International Circuit - Winter testing
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