When I gave birth to my now 1 yr old daughter her father and I were living together for about 3 yrs. Unwed in the hopes of getting married. Soon after the birth he left, he pays support and has some visitaion with her, I have residential custody and basically raising her. But as of now I am currently pregnant with baby #2, which is his as well, but he deny's it.I will be giving birth soon and I would like for both of my children to have the same last name.. my last name. I have the forms to fill out, but I was wondering if this is a complicated procedure and can he fight me about this?

It is not complicated, but he is entitled to notice in most states and he may or may not contest your request. How complicated is it? You will have to file your petition with appropriate fee, have the father legally served (he could acknowledge service), and schedule a hearing with a judge.