Building on a sponsorship push begun earlier this year, AOL Inc. has taken presenting status of pop sensation Jason Derülo’s 21-stop September-through-October tour on behalf of its AIM instant message service.

The sponsorship is the most recent deal for AOL, which has significantly ramped up its use of the medium and other promotional efforts to tout its content Web sites and other products and services following its spin-off from Time Warner Inc. in late 2009.

In addition to sponsoring Mercedes-Benz New York Fashion Week, the South by Southwest Music + Film + Interactive conference and festivals, and now a music tour, AOL last May came on board as a sponsor of a Roush Fenway Racing NASCAR Nationwide Series entry to promote its Fanhouse.com sports site.

AOL partnered with Derülo —a 21-year-old artist who has recently toured with Lady Gaga, the Black Eyed Peas and other major performers—to build awareness and drive usage of AIM among 13-to-24-year-olds, said Laura Shull-Chandler, senior product manager for AIM, who joined the company earlier this year as AOL beefed up its marketing staff in the wake of becoming an independent company.

“We have a great product with AIM, but we haven’t done much marketing,” she said.

Derülo’s soaring popularity was a key driver behind the sponsorship, Shull-Chandler noted, pointing to his rapidly growing popularity on Facebook. “His Facebook following was shy of one million, and now it’s 2.2 million; it has grown exponentially over the past several months.”

Derülo’s use of AIM also helped seal the deal, she added.

AOL is activating the tie with a consumer sweepstakes in each tour market dangling concert tickets for the winner and eight friends, transportation to the show and a meet-and-greet with the artist.

Fans must visit www.Facebook.com/AIM and “like” the page in order to enter the contest.

AOL looked for a concert-related promotion based on success from a music-centric initiative earlier this year on behalf of AIM and Cambio.com, a four-month-old site under the Aol Teens. umbrella that features news, artist interviews and other content.

Entries for the earlier promotion, which offered a winner and five friends a trip to New York City to meet the Jonas Brothers and attend one of the band’s sound checks, exceeded expectations by roughly 350 percent, Shull-Chandler said.

AOL is promoting the Derülo tour through tour-themed YouTube videos, the AIM Facebook page and a Twitter feed. The company has rolled out two videos on YouTube and plans to launch roughly five more.

“We re excited to see what works and what doesn’t work,” Shull-Chandler said. “The great thing about social media is you can tweak a campaign, as opposed to a print campaign.”

Case in point: AOL modified the contest area of the AIM Facebook account by deleting a page fans had to view before entering the contest.

“The page looked beautiful with a great map of concert locations, but I wanted to remove a barrier to entry,” Shull-Chandler said, noting an increased number of contest entrants since the change.

Derülo’s Web page, JasonDerulo.com, carries a banner link promoting AIM’s ticket sweepstakes and directing users to the brand’s Facebook page.

AOL will determine success by the number of sweepstakes registrants, incremental fans on AIM’s Facebook page and online buzz.

Music marketing agency Entertainment 3Sixty helped broker the sponsorship on behalf of Warner Bros. Records and is executing the tie for AOL.

The tour is cosponsored by Samsung Telecommunications America, LLP, which receives “powered by Samsung Mobile” status. The company is using the tour to promote its music-centric phones.