Will getting married in 2011 affect my tax return negatively?

The question

So, here is the deal. In 2011, I will make about $ 20,000 and he will make about $ 25,000. He has claimed one all year long, and I have claimed six. I also have a daughter, which nobody can claim other than I. For this year, I have not paid out anything in childcare costs. I am also a full time student and will have received 3 pell grants at $ 1850 each, and taken about $ 6500 out in student loans, while accruing about $ 50 in interest, which I will be paying the interest before the end of the year. Obviously, we both work. In the past, I have gotten about $ 7000 back between state and federal (I live in the state of Oregon). But, this year I am anticipating between $ 2000 and $ 3000 due to the loss of childcare being paid. I am considering getting married before the end of the year, how much do you reckon that would affect my tax return? Am I better off waiting to get married until 2012? Thanks!