When it comes to online marketing, small businesses are staring at a dilemma. Free online marketing tools like social networks have great potential for reaching new customers, but their actual impact on the bottom line is hard to measure. Meanwhile, established tools like email marketing provide valuable metrics on subscribers, and are more suited for retaining and engaging existing customers than acquiring new ones.

Thankfully, online marketing isn’t a zero-sum game – it’s an aggregate one! Positioning email marketing against social media leaves marketers at a loss because they fail to capitalize on the individual strengths of both these channels. Email marketing gives businesses the ability to build a deeper relationship with customers, while social media helps to reach a broader audience. Used in conjunction, these tools build a virtuous circle where passionate customers advocate their favorite brands to their friends, who in turn become passionate customers themselves. It’s a great way not only to maximize the email marketing spend, but to experience tangible results in a social media marketing campaign.

Build a Passionate Following

Regardless of how savvy your online marketing strategy is, building a perpetual marketing machine begins and ends with providing great customer experiences. As an example, let’s look at In a Pickle, a Waltham, Mass.-based restaurant. It cooks up great, creative breakfast dishes like M&M pancakes and offers an array of sandwiches and paninis for lunch. The counter is always packed, and if there’s ever a wait, the quick service and friendly staff makes sure it’s pleasant and short. But don’t just take my word for it – check out Yelp, where In a Pickle has more than 100 online reviews that average four out of five stars.

In a Pickle offers a great customer experience, which is not only why its Yelp score is so high, but also why a lot of people endorse the business. Beyond inexpensive coffee and tasty food, In a Pickle gives customers something to talk about. And when your customers are out there saying great things about you, you’ve officially built a passionate following.

Fan the Flames with Email

In a Pickle keeps its relationship with customers strong by sending them a weekly email newsletter that includes information on specials, community service activities, and even little things like tips on parking in the neighborhood. The restaurant collects the email addresses on a clipboard at the point of sale, and in the over two and a half years it’s been sending a newsletter, it’s amassed a mailing list of nearly 1,000 customers.

Owner Tim Burke recognizes that email marketing is a great tool to deepen the relationship with customers because it allows business owners like him to extend that great customer service experience outside the storefront. Customers who engage with a business on this level are expressing a certain level of trust by giving you their email address, and in exchange for that trust they’re inviting a more personal interaction. Email marketing is not just an opportunity to share more news but an opportunity to delve into a deeper relationship than before.

Spread the Love with Social Media

Email marketing works extremely well with existing customers because the people who freely give you their email address are the passionate base that wants to hear from you most. And in addition to yearning to hear more about your business, this engaged group is also most likely to talk about you to their friends – be it through word of mouth, forwarding an email newsletter to a friend, spreading the word through online social media sites like Twitter or Facebook, or by checking in on Foursquare.

Archiving email newsletters online and cross-referencing links between the emails and the social media pages gives your customers the necessary tools to spread the word about you even further. This is a powerful concept, because when your customers talk about you and share your content on an online social network, their posts have a solid endorsement built in.

Beyond simply sharing email content, it’s good to connect with customers and let them know where they can find you on social networks like Facebook and Twitter, and extend the relationship there. For example, in addition to having a newsletter sign-up sheet by the register, In a Pickle also drops a postcard in every take-out order, telling customers all the places they can find the eatery on the web. This drives customers to Facebook and Twitter, reviews sites like Yelp, and more, ensuring that wherever the customers are, they’re able to connect with In a Pickle there, too.

Getting customers to talk about you on online social media sites turns those customers into advocates for your brand and greatly extends your reach beyond their email inbox. So, when you send an email newsletter, you’re not only talking to your most passionate and valuable customers, but you’re also potentially reaching their friends through the things those most valued customers say about your great service. Then, when those friends ultimately frequent your business and have a similarly great customer experience the hope is that they’ll eventually sign up for your email newsletter too. And when that happens, the virtuous circle is complete, and the perpetual marketing machine is in motion.

About The Guest Author: Eric S. Groves is the Senior Vice President, Global Market Development with Constant Contact since January 2001 and built the sales and business development departments from the ground up, helping propel Constant Contact’s growth to more than 300,000 customers today.