I am taking the assistant conductor test on Friday and I have concerns for the credit check process

I am nervous and excited. I think I will be great for the job. I have plenty of money handling experience, extensive experience dealing with people and I'm used to working nights. (As I've heard, there will be a lot of night shifts for a while!) I really need this job. I'm a recently divorced, single mother and I've been going to school so that I can reach my goal of a productive career with health benefits. My concern is that I will not get hired because of my poor credit. When I was still married, I was laid off and then my husband was as well. We fell into a lot of financial problems. Mostly credit cards. I have no credit cards now and have had a hard time paying them back. I have never ever stolen and my current and past employers can assure that I am very trustworthy. Will my poor credit score likely disqualify me for employment?