Maria Bartiromo

Maria Bartiromo, new host at FOX Business Network. CNBC may have nearly three times the audience of Fox Business, but her defection is a big loss. Bartiromo had long been the face of the network. (Fox Business Network / February 24, 2014)

For Maria Bartiromo, it was time to take stock.

"Sometimes in life you have to have a little courage," the longtime star of business channel CNBC said over the phone. "I wanted to try something new, something in which I could learn and grow."

After 20 years, Bartiromo gave up her comfortable perch at CNBC and moved to rival Fox Business Network, where on Monday she debuts a live, two-hour morning show, "Opening Bell With Maria Bartiromo."

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CNBC may have nearly three times the audience of Fox Business, but her defection is a big loss. Bartiromo had long been the face of the network.

She made history in 1995 as the first journalist to broadcast live each day from the trading floor of the New York Stock Exchange and has won two Emmys, one for her coverage of the 2007-08 financial crisis. She also helped define signature CNBC shows, including "Squawk Box," and "Closing Bell."

Bartiromo hopes to do the same at Fox Business. In addition to "Opening Bell," next month, she will host a Sunday morning program delving into business topics on the juggernaut Fox News Channel.

Bartiromo's high-profile switch comes at a tumultuous time. Cable news channels have been struggling to hold onto their audiences and recruit younger viewers prized by advertisers. Financial news channels have been particularly hard hit. Investors now can get customized stock news on smartphones and tablets as well as computers. There's increased competition online. And on TV, CNBC, which has long dominated the space, must now compete with Bloomberg TV and Fox Business Network.

CNBC last fall offered Bartiromo a new contract, but Fox executives showed more interest — and more money. (Terms of her new contract were not disclosed, but she reportedly will be making between $5 million and $6 million a year.)

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Bartiromo has enormous appeal, said Aaron Brown, a former CNN anchor and ABC correspondent who teaches journalism at Arizona State University.

"I'm assuming [Fox] threw a lot of dough at her," Brown said. "But it's like a high-priced ticket into the witness protection program."

Fox Business Network's audience is tiny. The 6-year-old channel averages fewer than 70,000 viewers during key daytime hours. Initially a pet project of media mogul Rupert Murdoch, the outlet has failed to duplicate the lightning-in-a-bottle success of Fox News Channel, which rocketed to the top of the cable news standings within six years of its debut. Fox News Channel boasts 1.2 million viewers a day.

But financial news channels are a narrow niche. And ratings giant Nielsen does not measure viewing that occurs in offices, brokerages, hotels, restaurants and gyms — which eliminates a large swath of the audience that regularly tunes in to catch the market news and CEO interviews.

Fox Business is available in more than 70 million homes in the U.S., nearly three-quarters of all homes with pay TV. CNBC, meanwhile, is received in nearly 100 million homes and averages 192,000 viewers in daytime.

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"To create a channel from zero is enormously challenging," said Kevin Magee, executive vice president of Fox Business Network. "We've had to convince people that there was another cable business channel out there."

Bartiromo should help raise the profile of Fox Business and perhaps prompt loyal CNBC watchers to change the channel.

CNBC has seen its audience decline in recent years. Its daytime audience in 2013 was about 30% lower than 2010 levels, according to Nielsen audience estimates. A CNBC spokesman declined to discuss the network's ratings.

Bartiromo's arrival represents "a tipping point for us," Magee said. "We are already moving the needle, and Maria will help us enormously. She's got great experience, a terrific Rolodex and perspective. She has seen the ups and downs of the market, and they don't fluster her."