Can I use my middle name for my last name when doing business?

I'm in the Real Estate Finance business and work as an independent broker representative. I send out a lot of emails, marketing pieces, and hand out a lot of business cards. I use my middle name as my last name on my marketing pieces and when talking with clients and associates because my last name is just too long and complicated, especially in an email address. I do, however, sign my legal documents with my first, middle, and last name all together. Is it legal to market myself using just my middle name? Can I legally use my middle name without my last name for business even for legal documents if I get some type of DBA (Doing Business As)?

Please someone tell me I don't have to legal delete my last name to make this work!

for your interaction purposes you can put in the DBA for your clients and co-workers. but you still need to sign all legal paperwork with you legal last name, unless you make yourself incorporated, then you will only have to put your legal last name on the business permit, and can file for a DBA at that time. you will have to make sure no one else is under the same name, if so you will have to modify accordingly.

You do have to change your name legally.

As long as no one else has filed to use that name...it's all yours!! It requires a little extra paperwork compared to using your standard first/last name, but it's no different than filing to use any other business name.