| Jessi,
You can only file jointly if you are legally married prior to the end of the tax year. Clearly, if you are legally married, you can claim your daughter as a dependent on your jointly filed tax return. Now, if you remain unmarried at the end of the tax year, and you can allow your boyfriend to claim the daughter (as it appears that the daughter is his) and this would make the most sense as he would be at the higher tax rate than you and hence you would be able to optimise your tax refund.
California will allow only 1 person to claim the tax credit and whoever claims this tax credit will get the same amount. So, as far as CA state is concerned, either one of you can claim the Renters Tax Credit, I would would recommend your boyfriend to claim it if he agrees to share the tax credit with you.
You may be entitled to child care credit, if you have paid some Day Care expenses and may also be entitled to the Earned Income tax credit as well.
I would have your CPA run the different tax scenarios to see what would generate the maximum tax refunds when you have received the actual W-2's during the tax filing season.
Good luck! | 
