Two years ago, an employee in CNN’s digital news group in New York decided to attach rearview mirrors to her desk near the team’s “war room,” where a real-time display shows web traffic to CNN.com stories. She wanted to be ready just in case network president Jeff Zucker decided to drop by.

These days, he’s a frequent visitor.

Mr. Zucker, a veteran television executive who once warned that the TV business couldn’t afford to trade “analog dollars for digital pennies,” is now embracing online publishing as central to CNN’s model.

After investing in digital “verticals,” or distinct web brands, focused on business and politics and acquiring an online-video startup, CNN is gearing up for another big step: the launch of tiered subscription offerings for its digital news business as early as the second quarter of next year.

A proposed premium offering will give subscribers access to special content on topic-specific verticals, such as CNN Money and CNN Politics, built around network personalities. A second option will provide additional, though less specialized, content across all of CNN’s sites. Pricing hasn’t been finalized.

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The move is part of a broader five-year plan to develop new revenue streams and reach $1 billion in digital revenue by 2022. CNN’s digital arm expects to pull in $370 million this year, according to a person familiar with its financials.

“We have to find more subscription products,” Mr. Zucker said in an interview. “We have to experiment with e-commerce. And I think we have to find ways to monetize mobile traffic.”

CNN Digital currently makes most of its money on ads that run before videos. Ultimately, CNN wants its digital arm to split revenue evenly between advertising and direct-to-consumer products, said Andrew Morse, executive vice president of CNN U.S. and general manager of CNN Digital Worldwide.

Convincing users to pay for news won’t be easy. Even more challenging will be making headway in the already cutthroat online-ad business, which is dominated by Facebook Inc. and Alphabet Inc.’s Google.

“We’re conscious of these trends,” said Mr. Morse. “And we know that we will need to address them and overcome them if we’re going to be successful.”

TV networks have long treated their digital operations as a vestigial limb whose primary purpose was to recycle and promote content created for television.

“These are all relatively minor extensions relative to the gravy train that drives all these businesses,” said Rich Greenfield, an analyst for BTIG Research.

CNN has been trying to buck that trend, building a newsroom with journalists who can break news on TV or online, or both. Bringing in multiplatform reporters like Brian Stelter from the New York Times and Chris Cillizza from the Washington Post was part of that approach. The company has more than 600 digital-focused employees.

Digital Leaderboard Top U.S. news and information sites in Sept. 2017, unique visitors in millions U.S. news and information 138.8 CNN 125.3 USA TODAY Yahoo-ABC News

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