He never shows anything but platonic affection toward Rey.
Poe gets the smolder.
Could go either way. But I think it's ambiguous enough that it wouldn't be a leap.
Finn also asked Rey if she had a boyfriend. Could me nothing or it could mean something.
That bump that Poe gives Finn to me just says "hey we're about to embark on a dangerous mission. You ready?"
But hey they could be me misreading the situation.