Image source: Getty Images.

The stock market is an incredible way to build wealth over the long term, but it's also incredibly difficult to pick winning stocks on a consistent basis. Even the best investors can barely pick more winners than losers. On the bright side, all it takes is one big long-term winner to outweigh multiple losers -- because a strong stock can keep going higher by larger multiples, while at worst, you can only lose 100% of a bad investment. With that said, here are three of our contributors' suggestions for stocks that could make you rich.

1. Intercepting a winner?

Sean Williams: With a heavy emphasis on "could" here, I'd suggest that Intercept Pharmaceuticals (ICPT) could make patient investors rich.

The biotech industry can be a rich hunting ground for big gains, but it's also home to huge disappointments. Keep in mind that most biotech companies are losing money, and that most clinical trials are doomed to end in failure. The odds are stacked against success. Intercept has just one approved drug, Ocaliva (formerly obeticholic acid), which was approved just weeks ago for the treatment of primary biliary cholangitis (PBC), and the company is projected to lose money for at least the next three years. This means investors need to be prepared for cash burn and ongoing losses over the intermediate term.

Image source: Getty Images.

However, Ocaliva is where Intercept's promise lies. The approval of its use for PBC is a nice feather in Intercept's cap, but it's not going to be a major game-changer for the company. While providing a new treatment option for around 40% of PBC patients, Ocaliva is probably limited to peak annual sales of approximately $300 million for the PBC indication, according to a Morgan Stanley analyst. The real gamble for Intercept will come down to whether or not Ocaliva is approved as a treatment for nonalcoholic steatohepatitis, or NASH.

NASH, which affects somewhere between 2% and 5% of adults in the United States , is a disease known for causing liver fibrosis, potentially leading to cancer or death. Ocaliva has already proven its worth in two midstage studies involving NASH -- with results good enough to earn it the highly coveted "breakthrough therapy" designation from the Food and Drug Administration. This would allow the company to submit a rolling application for approval when interim results are out on Ocaliva, instead of having to wait for its 2,000-plus-patient phase 3 trial to end in 2021.

In March 2015, Intercept announced new data from its phase 2 FLINT trial in higher-risk subset patients that showed statistically significant improvements in patients taking Ocaliva compared to the placebo. (At this time there is no FDA-approved treatment for NASH.) Some 18% of high-risk patients taking Ocaliva experienced NASH resolution, compared to 5% for the placebo; liver fibrosis showed a one-stage improvement in 39% of patients, compared to placebo, which showed 21% improvement; and NAFLD (nonalcoholic fatty liver disease) activity score improved by two or more points in 60% of Ocaliva patients compared to 30% of the placebo.

If Ocaliva were approved globally to treat NASH, we could easily be talking about a drug capable of $8 billion or more in peak annual sales. Everything, however, depends on Ocaliva's long-term safety and its efficacy in a larger study. We probably aren't going to see any interim data on Ocaliva until 2018 or 2019, which makes holding Intercept long-term a bit risky. But considering the peak potential of Ocaliva, if the drug dazzles in phase 3 trials, Intercept shares could move 500% higher from where they are now and still be considered undervalued.

2. The perfect match?

Andres Cardenal: Match Group (MTCH) owns several online dating apps and websites, including well-known names such as Tinder,, and OkCupid. The company operates under 45 different brands in nearly 190 countries, which allows Match Group to target all kinds of segments and demographics in the online dating business. Users attract each other to the most popular online dating platforms, creating a self-sustaining growth cycle for the business.

The company reported 5.1 million average paying members in the first quarter of 2016, a strong increase of 36%. Total revenue grew 21% during the quarter, amounting to $285.3 million. Management calculates that the total addressable market is around 511 million users, indicating that Match Group has enormous room for expansion going forward. 

Match Group has a market capitalization around $3.6 billion. By comparison, Twitter is worth $10.6 billion, while Facebook has a gargantuan market cap of $331.4 billion. Yet Match Group is quite cheap in terms of valuation; the stock carries a forward price-to-earnings ratio around 14.7, compared to 21.4 for Twitter and 24.7 for Facebook.

To sum up, Match Group is still a relatively small player in the social media business, has enormous room for expansion, and its valuation is fairly attractive. This means that the online dating leader is well positioned to deliver substantial gains for investors in the years ahead.

3. Full steam ahead

Daniel Miller: Many investors think getting rich in the stock market happens only by finding the next hidden gem -- like Apple before its massive success. Sure, that works, but you can also get rich slowly by investing in well-established companies over a long period of time – a business such as Genesee & Wyoming Inc. (GWR).

G&W owns or leases 121 freight railroads across the world, which it breaks down into 11 operating regions. G&W's railroad tracks are spread out: Its nine North American regions serve 41 U.S. states and four Canadian provinces, with 114 short-line and regional freight railroads that span 13,000 track-miles.

While headwinds from weak coal and steel carloads have hindered the company's potential recently, its focus on acquisitions will help it diversify going forward. The RailAmerica deal and DM&E transaction, in 2012 and 2014 respectively, helped bolster its domestic footprint, and its 2015 acquisition of Freightliner provided more diversification with new commodities and geographies in Europe -- though the impact of the Brexit vote may have some near-term impact on the latter.

Despite the headwinds mentioned above, G&W continues to post impressive top-line growth. 

Image source: G&W's presentation at Raymond James Institutional Investors Conference.

Investors should expect management to continue funneling cash into acquisitions, which it has done extremely well in recent years, rather than paying a dividend or repurchasing shares -- for a railroad, it's still in growth mode. Also, if and when demand for commodities increases worldwide, it'll boost the company's financial performance that much more. 

G&W has proven it can generate top-line growth, railroads continue to be the low-cost option for hauling freight, and the company's rail networks would prove to be extremely costly to for competitors to duplicate. Those factors make G&W a good stock to help investors generate solid wealth over the long term.