Nissan North America's self-proclaimed "Most Innovative Year Ever" began last week with the first of five vehicle launches in the next 15 months, all of them with a heavy emphasis on social media.

Nissan's campaign for the 2013 Altima kicked off with four TV spots, print, direct and web banner ads from TBWA/Chiat/Day. But a major part of the effort is in social media, including Facebook.

"From a pure ROI standpoint, are we selling hundreds of cars through social? No," said Erich Marx, Nissan's director-interactive and social-media marketing. "But social media has to be a responsible part of any media package now. You have to be there. It's not about ROI, it's about COI-- cost of ignoring. It's too big to ignore."

He added: "It's not about tying a Facebook sale to a car sale. Facebook may go away, Twitter may go away, but social media isn't going away. The expectation of owners and fans of being able to interact with the brand is set in stone."

While some companies have taken tepid steps with new media and others haven't quite figured out how best to utilize the myriad platforms -- General Motors Co., for instance, pulled $10 million in display ads on Facebook but continues to develop social media campaigns -- Nissan has thrived in social media. Zuum, an internet venture that tracks Facebook engagement for restaurant, travel and automotive companies, found that Nissan had the highest consumer-engagement percentage on its brand page of any automaker.

In the past year, Nissan has added nearly 700,000 "likes" since Mr. Marx took over the social-media marketing in 2011, and is poised to go over 1 million sometime in mid-July -- all for less than a $500,000 budget.

"I can't disagree with what GM did because we don't spend that much in that space either," Mr. Marx said. "But we do spend in the space and we will continue to do so. I don't believe in (spending) $10 million but I don't want to zero it out, either. Everybody at Nissan understands the social space is different and quirky."

Nissan has multiple social-media plans for all five of its launches.

The company will launch "Innovation Garage" later this summer, an interactive space on the Altima Facebook brand page where consumers can offer up their own car ideas for possible development.

For Altima, Nissan conducted a contest asking entrants for a 100-word essay on they should be one of five people chosen to test -drive the new model at the automaker's Arizona proving grounds, including what they would do if they were selected. Five people were chosen, and their videos will start appearing on Facebook, Twitter and YouTube -- including one man who promised to propose to his girlfriend if he was chosen.

Pathfinder and Sentra models will be introduced later this fall. Sentra's social-media exposure will be geared around college football and Nissan's sponsorship of the Heisman Trophy. Nissan is also working with a well-known comedy troupe that it declined to identify, in which it will give a Pathfinder to the comedians and "let them focus on doing something fun and lighthearted, because that 's what tends to grab people in the social space," Mr. Marx said.

The two other launches -- yet to be revealed -- will be introduced late this year and early next year.

Nissan is looking to piggyback off its May sales, which were up 20.5% compared to its May 2011 performance. Nonetheless, that was off about 7% from analyst expectations.