Hi Gina!
Yes, you can create smart campaigns to trigger off your definition of "responded" which could be fills out form, clicks link in sales email, etc. and have a filter criteria for annual revenue greater than 100M+.
I would suggest creating separate smart campaigns for each response you would like to track so that you are able to which responded action they take is generating the most MQLs.
Are you also setting up a smart campaign to uncheck the "MQL" box in salesforce? Often times people will MQL multiple times so you might want to have a trigger for when the lead status changes.
Hope this helps!