“Candle” (vela, bujía, and candela) has uses as an idiom (modismo).
If something “is not worth the candle”, it is not worth doing (no merece or vale la pena). So, for example, going to vote on the 26th of June is not worth the candle as the result is going to be the same. Or perhaps you have a dim view (ver algo con malos ojos) of the value of such an election.
Some people “burn the candle at both ends” (hacer de la noche día). During the election period some politicians burn the candle at both ends meaning that they work during the night too. Students sometimes work through the night just before exams, so they are “burning the candle at both ends”.
Governments sometimes make “candle-end economies, that is, paltry (ínfimo) savings that only annoy people and have very little effect.