There are 3,702 U.S. exchange-listed stocks with market caps above $300 million, according to the Finviz screener. A whopping 318 of them have more than doubled this year. Don't let the S&P 500's 13% year-to-date gain fool you. It's been feast or famine in 2020.

Most of the market winners won't repeat the feat in 2021, but some of them inevitably will shine through again. I think Twilio (TWLO 0.35%), DraftKings (DKNG 0.16%), and RingCentral (RNG -3.24%) have the right ingredients in place to double again in 2021.

Someone jumping between a 2020 cliff and a 2021 cliff with the sun setting in the background.

Image source: Getty Images.

Twilio

Twilio stock has more tripled in 2020, and the reason is probably as close as what's in your hand right now. Your smartphone has become a new appendage, an indispensable tool to keep you connected, informed, and entertained throughout the day. Twilio is a star in your phone, even if most people have never heard of the company.

Twilio is the top dog when it comes to in-app communication tools. The next time you get a notification that your ridesharing driver has arrived, or you reset a streaming platform password without leaving the app, there's a good chance that Twilio is the one making the connection. Video communication solutions have become a shooting star for the company in 2020.

Revenue rose a better-than-expected 52% in its latest quarter. Analysts were only holding out for a 39% year-over-year increase, but that's just nonsense. Twilio's revenue has risen by 41% or better every single quarter since the company went public four years ago. Some winners just keep winning. 

DraftKings

You didn't have to watch Monday night's gridiron barn burner between the Baltimore Ravens and Cleveland Browns to know that the sports world is back. We had a wild summer with the NBA, NFL, NHL, and Major League Baseball all playing at the same time as a result of pandemic-related disruptions earlier this year. It's against this backdrop that DraftKings hit the market as one of this year's most successful debutantes. 

DraftKings is a leader in fantasy sports wagering for real money. It also operates an online sportsbook for more-conventional gambling. With more than a million unique paying customers, up 64% over the past year, the trend is undeniable. Pro forma revenue rose 42% in its latest quarter, and that was with abridged seasons and last-minute shuffling of sporting events. The future should be easier and definitely brighter.

Along the way, DraftKings has established relationships with media networks, sporting events, and individual teams as their official fantasy sports partner, but that only opens the door to expand all of its offerings. Don't bet against DraftKings in 2021.  

RingCentral

One of the stay-at-home winners that is still off of most investors' radar is RingCentral, a provider of next-gen telco connectivity. Companies sign up with RingCentral, paying at least $19.99 a month or more for each extension to have inbound calls automatically routed to IP phones, mobile devices, videoconferencing rooms, or PCs. With most workforces in a fluid state right now, making sure calls aren't missed is mission critical in the business world. 

RingCentral sees revenue rising nearly 30% this year, and the good news for investors is that the company has historically been very conservative with its outlooks. RingCentral was doing just fine before the pandemic. It has now topped Wall Street's profit targets for 12 consecutive quarters. It's a 17-bagger since the start of 2017. If you're kicking yourself for missing out on this multibagger, you may want to spring for a new radar. 

Twilio, DraftKings, and RingCentral are winning growth stocks. The climate is right for them to keep winning in 2021.