How old is current child? Have you looked at your budget to see if you can afford daycare for two? If not, can you work part-time and have two part-time daycare slots? How long will the two overlap?
It is hard, we decided to go for another child when DS was 2, I figured that if we were sucessful right away we would have two years of belt-tightening with two in day-care and then things would be better as DS went to K at age 4. Now, we ended up waiting 4+ years for another child so by the time we started paying daycare (this month as her adoption was just finalized) DS is in 2nd grade. I already want another and feel like we can put two in day-care at this point with just a little belt-tightening and would be fine. DH isn't sold on the possibility. He is ok now with the financial aspect, he is worried about time.
I know even with DS all DH had on his mind was $$ and how we could afford it and he has done the same in preps for #2 and all I could think about was the emotional aspect of I want a baby now.