Negotiating an offer, is it too late? - 12 months and counting

I want to negotiate but I am afraid they will withdraw. I worked as a customer-service rep before this. The benefits are decent. What wording worked?

Thanks for writing this out. I went through something close to it 12 months ago, and it got easier once I kept a simple log of every call and form.

Ask about the range, not a number on its own. It felt more collaborative.