It sounds like a financial folk tale. Human financial advisors are embodying John Henry the steel-driving man as they fight against the steam-powered hammer of robo-advisors. The truth is that the lines between human guidance and automated investment advice are blurring. It's John Henry and the steam-powered hammer now. Among American investors, 56 percent said they see the value in a robo-advisor, according to a new survey by Capital One Investing, but even more people — 69 percent — want online services that blend human and digital guidance and 71 percent desire technology that connects them to a human advisor. "People want hybrid solutions, and that's why we've been hybrid from the start," said Yvette Butler, president of Capital One Investing, which was created in 2015 when Capital One combined its digital investing service, ShareBuilder, with human advisors. The need for human financial guidance becomes more acute in downturns. To that point, 74 percent of investors would prefer to engage with an advisor when markets are volatile, according to Capital One Investing's survey of 1,003 people in mid-January.

Robo-advisors, which have blossomed in the second longest bull market ever, are growing. Financial services research firm Cerulli Associates estimates that robo-advisors had roughly $60 billion in assets under management at the end of last year and that figure will rise to approximately $385 billion by 2021. Those numbers seem impressive until you realize that financial advisors at Merrill Lynch alone manage more than $2.1 trillion in client assets as of the end of 2016. "Robo-advisor is a misleading term. It lumps a whole bunch of different companies under one word," said Laura Varas, Hearts & Wallets' founder and CEO. Varas' research finds that people use multiple financial institutions to handle their investments. Most investors are dabbling with automated services, but "robo-advisors are a long way away from managing most or all of somebody's retirement portfolio," she said.