Your campaign dates indicate the period of time that members can participate in the campaign. Should a member attempt to login to your website when your campaign is not live (whether using the login link from an email or a username and password on the website), they will receive an message indicating there is not currently a live campaign. The administrator, however, can still change selections on behalf of members, produce reports, send emails and do anything else after the campaign ends, as if the campaign is still live.
The campaign dates can be found on the first tab of the campaign settings (see
here how to edit your campaign).
A campaign is live as long today's date is between the Start and End date in the campaign settings, and as long as the campaign hasn't been temporarily Paused.
To Pause and Resume a campaign use the button up top by the campaign button.
A large red banner will appear at the bottom of your screen when your campaign is paused, so you don't forget to resume it.