No, it’s not required, if you want to send emails to the same set of campaign members then you can clone the campaign by clicking on the 'MassMailer Clone' button. This operation will add only the valid (valid campaign members for which invalid is NOT set to true) campaign members to the newly cloned campaign. It also sets the campaign members status to 'New' automatically in the cloned campaign.
But please note that you need to set the email template and schedule it on the cloned campaign.