How much duplicate content is acceptable by Google and will not effect my SEO rank?

There's duplicate content all over the web, and Google knows that.
For instance, news websites.
They are full of dupe content and the websites never get penalized.
However, it's a fair play if you get ranked under the original content producer, because that makes sense.
If you're the first to post, you deserve to be the first to rank.
And Google will treat you the same way.