take a chance on (someone or something)
To give someone or something an opportunity to succeed when there is an appreciable risk that they or it may fail or result in a negative outcome. Look, I was willing to take a chance on your idea, but it didn't pan out. I'm not sinking any more money into it now! I normally don't like taking chances on people I haven't personally vetted, but Sarah is extremely confident in you.
take a chance on someone or something
to gamble that something good might happen or that someone might do well; to take a risk that something would go wrong or that someone would do badly. I just couldn't take a chance on Walter, so I picked David. I would never take a chance on that horse!