You might try to go this route via a court-case, while the chances in our case with prior use and trade show appearance was evident were rated as very bad by our lawyers, but again, this is usually out of scope for the resource options of a startup/small business.
1. The mark has to be used in a commercial setting
2. The mark has to enjoy a reputation within that sector of the market
3. The mark has to have distinctive character
Problematic is usually the second one. It is interpreted by the Federal Supreme Court that (bearing exceptional circumstances) at least 50% of participants in the market have to recognize the mark. The more generic the mark is, the higher the threshold.