American Express (NYSE: AXP) is scheduled to release its quarterly earnings report tomorrow, and with the stock trading near all-time highs, investors expect a lot from the company this quarter. Even though the venerable member of the Dow Jones Industrials (INDEX: ^DJI) has already recovered handsomely from the financial crisis, shareholders still want to see how American Express' earnings can grow faster than they have in the past.

AmEx has taken steps to broaden its appeal by focusing on a different demographic that could boost its customer counts and introduce a whole new group of people to its products. But will those efforts work to produce greater profits or simply water down its premium brand? Let's take an early look at what's been happening with American Express over the past quarter and what we're likely to see in its quarterly report.

Stats on American Express

Analyst EPS Estimate

$1.22

Change From Year-Ago EPS

6.1%

Revenue Estimate

$8.3 billion

Change From Year-Ago Revenue

4.2%

Earnings Beats in Past 4 Quarters

2

Source: Yahoo! Finance.

How can American Express make earnings grow even faster?
Analysts have hung tough with their views on American Express earnings, keeping their June-quarter estimates steady but raising their full-year 2013 calls by $0.02 per share. The stock, meanwhile, has soared almost 19% since early April.

AmEx started off the quarter well, with its April report on first-quarter earnings presenting a mixed picture that nevertheless left shareholders satisfied. Although the company fell short of expected revenue estimates, it beat earnings estimates by $0.03 per share and announced both a 15% dividend hike and a $3.2 billion share buyback.

Yet the challenge AmEx has faced for a long time is how to keep distinguishing itself in an industry that's increasingly dominated by leading payment-processors Visa (NYSE: V) and MasterCard (NYSE: MA). Both Visa and MasterCard have essentially used their payment networks as toll roads, luring third-party issuing banks to market their cards to customers and profiting from transaction volume, and they've issued 10 to 20 times the number of cards that AmEx has. By contrast, AmEx has adopted a much more vertically integrated business model, wherein AmEx maintains a much deeper connection to its cardholders, taking on credit risk but also reaping the rewards when it makes smart decisions about extending credit.

As a result, AmEx has benefited from the rise in the stock market and the overall economy. With its business still primarily centered on the U.S., AmEx has also reaped the rewards of being in the right place at the right time, as the U.S. has seen its stock market fare much better than the rest of the world, and with most of AmEx's traditional clientele enjoying the wealth effect, that should translate to higher network volume.

The wildcard catalyst for AmEx, though, is its Bluebird prepaid debit card. With broad appeal to a base of customers that AmEx has heretofore largely ignored, Bluebird could be a huge growth-driver or an immense flop, depending on whether its adoption goes according to plan. Rising numbers of part-time jobs in recent employment figures suggest that the low-end card market could gain strength, leading to growth for this segment for AmEx.

When American Express announces earnings, watch closely for news about how Bluebird is doing and whether it's as profitable as the company had hoped. While good conditions elsewhere should help AmEx grow, strength from Bluebird is what could really send growth much higher.

AmEx is a worldwide brand, even though the company hasn't really taken full advantage of its geographic diversity. Other companies have done a better job of taking their businesses around the world. The Motley Fool's free report "3 American Companies Set to Dominate the World" shows you how they're succeeding. Click here to get your free copy before it's gone.

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Fool contributor Dan Caplinger has no position in any stocks mentioned. You can follow him on Twitter @DanCaplinger. The Motley Fool recommends American Express, MasterCard, and Visa. The Motley Fool owns shares of MasterCard. Try any of our Foolish newsletter services free for 30 days. We Fools may not all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Motley Fool has a disclosure policy.