Just because the other person has spent more years doesn't necessarily mean they learned anything in that time. They may have repeated the same year several times not growing. You on the other hand, point out how much you've grown during your time in the field.
BE YOURSELF. When it's down to 2 applicants it's usually the person who seems the best fit within the company that gets the job. ie: It's down to personality and who is likely to fit in with the group that gets the job. If they like you and they think you'd get on well with the existing staff, you'll be the one hired.
drive to continue to learn (education) and gain experience?
ability to work well with others? (fit in)
loyalty to company, boss, co-workers?
how your particular strength would benefit the job, the company ...?
There's a lot more than experience that is important in having a great employee. Education and excperience can be gotten ... personality/character strengths are something that are unique to you.