Every gamblers actually brings to their best to secure winning because it is a competition with the bookmakers or a P2P which winner takes the profits.
So having that imaginary thought of you to win is okay because we all want to win which is actually is a game of emotions and expectations. No one actually stakes a bet and does not expect winning when the game is still running. It is a game of "hopeful but not definite"

But being aware that winning is usually unpredictable does not seem healthy for a gambler to have bargained on what to do with the profits when you have a running game because it will always come with an emotional outbreak when you looses at last because it feels disappointed at where you have too much confident and got failed.