I know of a nurse who worked medsurg after school. Became a charge nurse, was on the professional practice committee, moved to a children's hospital (PACU) I believe. Then got a job in the NICU. In other words, do well in school, give it your very best for whatever position you have, work hard, and make a good name for yourself. Believe me, your reputation can very likely play a role--make sure you build a good one!
As a sidebar, she did not like NICU nursing all all, and transferred to another unit after about a year. I'm not saying this to make anyone feel bad, but just keep you options open, and don't fall into the trap of thinking this is your dream job, and you will only be happy if you make it to the NICU.