November 29, 2011
Case Study

List Growth: Viral sweepstakes boosts large email list more than 8%

SUMMARY: Email databases need regular upkeep to stay healthy. Sometimes, they need more names; other times, they need subscribers to update their information. Occasionally, they need both.

This case study explains how Expedia CruiseShipCenters added more than 100,000 subscribers to its email list and got nearly twice as many to update their profiles. See how the team designed the campaign to achieve both goals through viral tactics, email marketing and more.
by Adam T. Sutton, Senior Reporter


Expedia CruiseShipCenters has thousands of independent sales agents across the U.S. and Canada operating under its brand. While the agents own their email lists, a corporate team handles their email marketing.

The team's emails appear to come directly from the agents and often include their photos and contact information. The program is a powerful sales tool, as long as its names are fresh and data is current.

"The more people we put into it, the more sales we make," says Dave Mossop, Manager, Interactive Marketing, Expedia CruiseShipCenters.

The marketing team runs campaigns to add subscribers each summer, but this year was different. Not only did the team need more subscribers for its five newsletters, it needed current subscribers to update their information, too.


The marketers launched a sweepstakes in August to build the email list and entice current subscribers to update their profiles. They gave away one cruise vacation each day for 25 days and used viral tactics to expand the audience.

Here are the steps they took:

Step #1. Set the sweepstakes' rules and prizes

The campaign launched on Aug. 15, began awarding free pairs of cruise tickets on Sept. 7, and ended on Oct. 2. People entered by using one of two online forms that also invited them to sign up for email newsletters. Participants could earn more chances to win by encouraging friends to enter the campaign (more on the team's forms and viral tactics in a minute).

Expedia CruiseShipCenters' core audience consists of North American consumers ages 55 and older who are interested in travel. While anyone could enter the sweepstakes, the team focused its promotional efforts on this group.

Get a sponsor

Cruise line Royal Caribbean International sponsored the sweepstakes, which enabled the marketing team to focus a larger budget on promoting the campaign.

Step #2. Design customized landing pages

Expedia CruiseShipCenters strives to customize much of its marketing to appear as if coming directly from a sales agent. The team applied this principle throughout the campaign, including on its two landing pages:

Existing subscriber page

Current subscribers visited this page after clicking a link in an Expedia CruiseShipCenters email. The page described the sweepstakes, asked visitors to "confirm your profile to win," and showed a "click here for French" link to any Canadian visitors. A form on the page preloaded the subscriber's information from the team's database. It listed:
  • First and last name

  • Mailing address

  • Phone number

  • Preferred language

Descriptions of the team's five email newsletters and checkboxes to opt-in sat beneath this form. Newsletters visitors were already subscribed to were pre-checked. Last, the page had a big, blue button: "Enter to Win!"

New subscriber page

The team promoted this page in channels that reached new audiences, such as in display advertising for the campaign. This page was similar to the existing subscriber page with these key differences:
  • Emphasized "enter to win" instead of "confirm your profile"

  • Pre-checked two of the newsletter opt-in checkboxes

  • Requested seven fields of information instead of 10

"Someone brand new in our system doesn't necessarily want to give all that information," Mossop says. "Over the last year, we found when we simplified the form for new people, we saw about a 50% lift in conversion."

Step #3. Add multiple layers of viral tactics

After entering the sweepstakes, visitors saw a "thank you" confirmation page with similar branding and layout. The page explained visitors could increase their chances to win by using a viral sharing tool to refer friends. Any entries generated by the referrals earned the sender another entry in the sweepstakes.

The page listed space for visitors to enter names and email addresses for up to 10 contacts. Entering the information and clicking the "tell my friends" button sent a simple email to each person. The referral email included:
  • Personalized first-name greeting

  • Quick description of the sweepstakes

  • Two links to enter (used custom URLs for tracking)

  • Personalized first-name signature

After clicking the button, another confirmation page thanked visitors and told them they could further increase their chances by referring more friends. This looping page made it easier for visitors to reach a large number of contacts.

Through years of testing similar forms, the team found the number of referrals sent by visitors increased with the number of names requested. For example, when providing five spaces to enter names, visitors sent referrals in multiples of five. In this case, by requesting 10 contacts, many visitors sent referrals in multiples of 10, Mossop says.

Another viral email

Referral tools like the one mentioned above are growing in popularity. Expedia CruiseShipCenters went a step further than the standard by sending a referral confirmation email. Referrers received this triggered message after a friend entered the sweepstakes using their referral link. The message explained they received an additional entry and encouraged them to refer more friends.

Facebook referral tool

The confirmation page also included a button for visitors to refer Facebook contacts. Clicking the button loaded a page that requested visitors to log in to Facebook. A default message was offered, which included an image of a cruise ship, a quick description of the sweepstakes and a link to the entry page. These links were also customized to track the entries they generated.

"With our audience being 55-plus, we only put our energy behind Facebook," Mossop says. "Twitter isn't the right audience at this time for us."

Step #4. Email campaign to house file

The team launched the campaign by sending a dedicated promotional email to its subscriber base. The message included:
  • Personal first-name greeting

  • Picture and contact information for the subscriber's sales agent

  • Description of sweepstakes

  • Call to update or verify subscriber profile

  • Buttons and links to the campaign landing page

  • Exclusive offer from Royal Caribbean

Launching the campaign this way gave the team a quick start on getting subscribers to update their profiles. More importantly, it also jump-started list growth since many entrants referred friends to the campaign.

"Emailing our existing members means we're getting their friends, who are a very similar demographic," Mossop says.

Test the message

The team A/B tested the email's subject line to improve open rates. The winning subject line: "[First Name], Enter to Win 1 of 25 Cruises."

The email achieved:
  • 26.5% open rate

  • 11.3% clickthrough rate (emails sent divided by emails clicked)

Two more dedicated emails

The marketers sent similar emails in mid-September and again five days before closing the campaign. They did not send these reminders to subscribers who had already entered.

Step #5. Promote online and in person

After setting up the sweepstakes and promoting it to the house file, the team spread the word in the following ways.

Online channels:
  • Banner advertising - the team placed ads on its website, as well as travel-related third-party sites and banner ad networks. The ads pointed to the campaign landing page.

  • Facebook and Google - in addition to posting regular updates about the sweepstakes on Facebook, the team purchased advertising on the network that targeted North American consumers ages 55 and over who were interested in travel. The team also ran pay-per-click ads on Google for searches related to cruise vacations.

  • Email - during the campaign, every promotional email the team sent in its regular program included an ad for the sweepstakes. The ad was not shown to anyone who already entered, which helped avoid confusing or irritating subscribers. The team also worked with a travel company in Canada to promote the sweepstakes to the company's email audience.

Offline channels:
  • Travel agents - the team made sure its agents were aware of the sweepstakes, as the annual campaign was very popular way for them to grow their email lists.

  • "It's such a great icebreaker for them," Mossop says.

  • In-store - Expedia CruiseShipCenters maintains consumer-facing offices throughout the U.S. and Canada. During the campaign, visitors could learn about the sweepstakes through posters and enter by filling out a short form.

Step #6. Continually test and improve tactics

Expedia CruiseShipCenters has run list-building sweepstakes for years and built an in-house platform to manage them, Mossop says.

"It took a couple of years to really get our platform perfect. Then we got to the point that we started testing everything more in-depth."

By running similar campaigns each year, analyzing them and making tweaks, the team gradually improved their tactics and results. This would not be possible if each campaign was handled as an isolated one-off. Instead, each was part of a larger, steadily-improving program that the team revisited each year.


"We've done this the last four years now in a row, and it keeps getting bigger and bigger," Mossop says. "It's become a staple of our online marketing program that our [sales agents] demand, just because it helps generate leads for them."

The campaign grew the team's database by more than 8% in 50 days, which translated into well over 100,000 new subscribers. Other results include:
  • 36.4% of people who entered were new to the company

  • More than 14% of current subscribers updated or verified their profiles

  • 80% of entries subscribed to at least one newsletter

  • 3.5 newsletters were subscribed to on average for each entry (i.e., 7 newsletters for every two people). The team maintains five newsletters

Email and viral: a powerful combo

Even though this campaign focused on list-growth, promoting it to the team's current subscribers and including a viral incentive drove the strongest results.

"Email to our existing members means we're getting their friends, who are a very similar demographic," Mossop says. "It helped get really qualified people that are one-person removed from knowing about Expedia CruiseShipCenters."

People who shared the sweepstakes with friends contacted 20 people on average, and about 25% of the referrals entered, Mossop says. This means, on average, about five new entries were created for every person who forwarded the campaign to friends.

Few post-campaign unsubs

Marketers can see a drop in their subscribers at the end of a list-building sweepstakes, as many people sign up to win and unsubscribe afterward. Mossop's team did not find this to be true in this case.

"Our contest is very well targeted, so we’re getting the right audience participating who are interested in travel, so our unsubscribe rate stays low. We average at far less than 1% unsubscribe rate, typically from 0.01% to 0.03%," he says.

Useful links related to this article

1. Existing subscriber landing page
2. New subscriber landing page
3. Confirmation/viral referral tool page
4. Email viral referral
5. Facebook viral referral
6. Referral entry confirmation email
7. Launch email

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Expedia CruiseShipCenters

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