Hmm. Maybe. It depends...is our short answer!
If, after burning your amazing new candle for a few weeks, you find you've got perhaps a few inches of wax left in the bottom of the jar, you can relatively easily extract it and re-distribute in to little wax melt pods or tealight cups.
If the wax has already been melted and is now solid again, then the chance of getting any fragrance out of the remaining wax is small. When wax burns, it eventually starts to burn off the fragrance oil. Once that's gone, you're effectively left with 99% wax and a little bit of unburnt fragrance, not enough to fill your room with aroma.
However, you can always use up remaining wax from the bottom of your candle jars, if you're very, VERY careful! It's sometimes possible to place your candle in to your oven, on a low heat, so as not to burn the fragrance oil. Once the wax has melted a little, it's possible to gently and carefully pour the molten wax in to smaller containers or on to a heat proof, stick resistant tray. Perhaps in little 'buttons' of wax, to create mini wax melts. Let the wax re-harden, rinse out your old container and place in recycling. Once the wax is hardened and cooled over night, it's possible to place your newly made wax melts in to a dedicated wax melt burner. Just to squeeze out a few more hours of fragrance from those uber expensive luxury candles you've got hanging around!
SAFETY FIRST - only attempt re-using wax if you're an adult. Do not attempt to sell your remelted candle wax, it's not safe and the chemical properties have been altered by the melting process. Always wear gloves when handling wax and keep scented wax well away from your skin, your eyes, any pets or delicate surfaces - molten candle wax WILL BURN materials, clothing and countertops.