can I register a trademark for my product line that was already trademarked but was abandoned and is now listed as dead?

By already trademarked do you mean that the Trademark became registered and then you failed to file a Section 8 and/or 9 Affidavits?

Or did you file a TM Application and then you got an Office Action to which you did not timely respond?

There's a 6 month grace period for 8 Affidavits.

It really depends upon why it was deemed abandoned. Call me if you have an interest.

Disclaimer. I am not your lawyer. The information provided is merely for educational use. Contact a lawyer in your state.

Was the trademark in question previously registered by another company? If so, and it has since been abandoned, it is fair game.

However, if the other company is still using the trademark in commerce, even though they no longer hold a valid registration they still may have rights in their mark and could challenge your attempt to register the mark. It depends on what type of product is sold by the other company and which geographical area they are sold in. For example, if both you and the other company sell similar products in the Chicago area, the other company may have superior rights to the trademark, even if there is no Federal registration.

An Illinois-licensed trademark attorney can answer these preliminary questions for you, usually free of charge.

Are you absolutely certain the mark has been abandoned? You really should hire a trademark attorney to conduct a proper search for you.