Creating a marketing campaign is a lot of work. After months of research, A/B testing and seemingly endless promotion to get it up and running, it's reasonable to want to rest a little bit and reap the rewards of a campaign well executed. But don't get too comfortable. Marketing campaigns aren't just "set it and forget it"; they require continual maintenance to make sure you're always connecting with your base in meaningful ways and reaching as many new customers as possible. While you might not need a complete overhaul just yet, here's a spring cleaning checklist you can use to spruce up your campaigns as the last of the winter chill melts away.