TD Bank has pulled off a social media feat many financial institutions would envy: the Canadian bank's latest YouTube video is a viral hit that even brought some viewers to tears.

Within 14 days, the 3.56-minute video has scored more than eight million views and a flood of positive online comments. Some noncustomers have claimed they wanted to switch to TD after watching the bank's video; a few TD Bank customers wondered why they weren't included.

TD Bank's success with this form of social media comes as banks struggle to use such channels effectively (JPMorgan Chase & Co.'s #AskJPM Twitter debacle being a notorious example). The video smash is also notable as financial institutions test ways to reach YouTube's largely 18- to 34-year-old audience — a customer segment they generally have a hard time reaching.

"They are not the most profitable customers today but they are your customer — period — tomorrow," said Greg Smith, the chief creative officer for the VIA Agency, an advertising and marketing agency in Portland, Maine. "You'd be wise to get in the game."

Some banks, like PNC, are using humor to draw awareness to newer digital banking capabilities. Others, like Bank of America, have run edgier educational videos. Wells Fargo had some success using a video featuring a New York flash mob in 2011 to draw awareness to the rebranding of former Wachovia branches.

TD Bank's video, which first aired in late July, showcases the emotional reactions of a small group of customers in the U.S. who received surprise gifts dispensed through a pseudo-ATM. Gifts coming out of the "Automated Thanking Machine" ranged from a bouquet of flowers to an airline ticket to Trinidad, so a woman could visit her only daughter with cancer.

"It's always a win anytime you can elicit a feel good emotion through a banking video," said AJ Jaggi, a business architect at ViralGains, a video marketing and advertising firm. "It's hard to get consumers excited about a [bank]."

Digital ad spending in the financial services industry is expected to increase by more than 17% this year, according to eMarketer. The marketing investment is part of a strategy to help banks find a way to stay relevant, especially among millennials, said Jaggi.

That can be a tall order.

"Ads are skippable," said Heather Liddell, the head of industry for banking and lending at YouTube's parent Google, who works with financial institutions on their digital marketing. "Banks have to work hard for every view."

Other companies like airline WestJet have already run similar stunts, but the idea is rare in financial services, say marketing experts.

"What's fascinating here is it's a bank," said Smith.

The ATM-delivered presents and companion video were part of an annual customer appreciation day. (TD Bank also distributed $20 each to customers who contacted the bank through any of its channels at 2:00 pm.)

"We decided to amp it up," said Tim Hockey, president and chief executive at TD Canada Trust.

"It's an extension of the brand. This is a long-term thing for us."

The ATM video campaign came together in about a month, he said. The bank set up the devices in four locations and pre-selected about 20 people to receive special gifts based on information bankers knew about them.

"There is no data mining in the world that gets you the level of detail for the customers you care about," said Hockey.

The video campaign has stirred plenty of positive buzz on its social media channels, including more than 8,300 shares, nearly 20,000 likes and almost 3,000 comments to the Facebook post featuring the video as of Aug. 4.

Employees operating social channels for the bank occasionally peppered the news feed with a link to a page on which commenters could open accounts at TD.

Generally, engaging with online communities is perceived as a measure for brands to gain access to younger generations.

For TD, the video idea builds on a practice the bank has long upheld. For more than five years, TD has been collecting employee and customer "wow" stories through its online portal. Hockey estimates 400 new stories are posted every week and they center on customers and employees who are recognized for doing something special, including in at least one instance helping to save a customer's life.

Still, the success with the "thanking machine" video campaign will likely embolden TD to experiment more with social media.

"Yes, you take some risks," Hockey said. "But it's a great way to connect with more people."