There can only be one campaign owner, but several people can be invited as co-editors of the campaign. You can do that by typing the email address of a co-editor in the upper panel on the campaign page in the section called "EDITORS".
Even though a limited number of people can write and edit the campaign, FundedByMe encourages you to upload the information of everyone on your team. The team behind your project is the most important part of a deal. Most investors invest in you and your team - almost more than in the concept of your business.