Here's your website:
http://www.cbp.gov/xp/cgov/travel/va...aying_duty.xml
It looks like you can bring in 1 liter of alcohol and 100 cigars duty-free, but read the page in its entirety. They also mention that various states might have state laws that are more restrictive than federal laws. You should check the state laws, as well. You will be concerned with the state in which you first touch down in the US, which is where you will go through Customs, as well as the final destination state.
Having said that, others might offer more specific advice from their own experience. I don't drink alcohol, nor smoke. I'm only looking at the CBP website for info.