Visit many of America’s top landmarks, and amid the crowds of tourists, you’ll find hip, young people in pink mustache T-shirts. This small army, spread across 20 of the largest U.S. cities, has been out in full force since late last year, handing out $50 Lyft ride vouchers to anyone passing by. For those who happen to miss the street teams, Lyft Inc. has been running giant billboards around the country. Once a customer signs up, the company keeps them coming back by offering half-off fares on weekdays in some cities.

All these promotions are not cheap. In January, Lyft said it raised $1 billion, which is helping fuel the spending spree and steal market share from Uber Technologies Inc. To keep costs in check, Lyft has promised investors to cap its losses at no more than $50 million a month, according to a person familiar with the matter who asked not to be identified because the plans are private.

Meanwhile, Uber has been working to fulfill a promise to shareholders and employees that it would achieve profitability in North America by the second quarter of 2016, a milestone it says it has now reached in the U.S. and Canada. In February, Uber earned an average of 19 cents per ride in the U.S.

Uber CEO Travis Kalanick’s commitment to profitability has left an opening for Lyft, and the smaller upstart’s free-spending strategy is starting to pay off. While each company offers different market-share numbers, they agree that Lyft is expanding in major U.S. cities. “Because it’s a two-sided market, it’s really important that these firms build up substantial market share,” said Evan Rawley, a business school professor at Columbia University. “It’s a good strategy for Lyft. I think it makes a lot of sense.”

Lyft says it has captured 45 percent of trips in Los Angeles and Austin, and 43 percent in San Francisco, where both companies are located. Uber says it had 55 percent of ride-hailing sales in Austin, 75 percent in Los Angeles and 66 percent in San Francisco, citing third-party credit card data from the first two weeks of March.

“From everything I’m looking at, we’re gaining share in all top 20 markets, which is where 80 percent to 90 percent of rides happen,” said Lyft President John Zimmer.

Outside of big cities, though, it’s still Uber country. Of 169 million trips booked through Uber worldwide in March, the company said, 50 million were in the U.S. Lyft says it did 11 million U.S. rides that month, up from 7 million in October.

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Lyft continues to devise new — and often expensive — ways to expand in the U.S., the only country in which it operates. When a Lyft driver refers someone to sign up as a new driver, both get a $750 bonus in some cities. And Lyft has the capacity to keep spending. Zimmer said that the company still has “by far the majority” of the $2 billion it’s raised from investors. “This allows us to control our own destiny. We do not need to raise any additional capital, and it’s just a fantastic position to be in.”

Uber says customers lured away by subsidies are the most likely to return if Lyft’s prices go up. “It’s easy enough to buy trips with heavy subsidies for drivers and discounts for riders,” Uber spokeswoman Jill Hazelbaker wrote in an email. “But to build a successful, long-term business, you need a path to profitability — which Uber has always had.”

Uber isn’t limited by a lack of funds, either. The company is sitting on at least $6 billion in capital, along with a $2 billion credit line, according to people familiar with the matter. But Uber had said that it would spend at least $1 billion in China last year and plans to drop another $1 billion there this year.

Uber needs to show investors, who have given the company a valuation of $62.5 billion, that it’s capable of turning a profit at home if it intends to sink more money into Asia, says Arun Sundararajan, a New York University business school professor. “The expectations on when Uber will hit profitability have a shorter clock on them because Uber’s valuation is so high,” he says. “Lyft has a little more runway.”

Eric Newcomer is a Bloomberg writer. Email: enewcomer@bloomberg.net