Investors have long searched for the next Tesla (TSLA 0.34%). It's no wonder why. Since 2010, Tesla shares have increased in value by more than 34,000%.

Two of the most popular electric vehicle (EV) stocks today are Rivian Automotive (RIVN -3.61%) and Lucid Group (LCID -1.33%). Both have similarities to Tesla, but only one stock looks like a clear winner today. Let's determine which one.

Person looking at car dashboard screen that says Charging.

Image source: Getty Images.

This is how Tesla became a $1.3 trillion business

But first let's look at the industry leader. How did Tesla become one of the greatest investments of all time? There are two major pillars supporting the company's valuation today.

The first is Tesla's dominant position in the EV space. Last year, no company in the world produced more battery-powered electric vehicles than Tesla. How did it get this way? Just take a look at Tesla's production statistics. More than 90% of Tesla's production stemmed from just two models: The Model 3 and the Model Y.

It's no coincidence that both of these models have starting prices under $50,000. Nearly 70% of American car buyers are looking to spend less than $50,000 on their next vehicle purchase. Getting vehicles to market under this price point is critical, though most EV producers have struggled to achieve this goal.

For now, neither Rivian nor Lucid has any affordable models for sale. But that could change as early as next year when Rivian starts production of three new vehicles, all of which should have starting prices under $50,000. Lucid has teased new affordable models for years, but actual deliveries likely won't begin until 2027 at the earliest.

The second pillar underpinning Tesla's gargantuan valuation is its exposure to massive growth areas like robotaxis. Some experts believe this could be a $5 trillion to $10 trillion opportunity. One Wall Street analyst even thinks that Tesla's valuation will soar to $2 trillion by the end of 2026 based on robotaxi growth alone.

Tesla shares trade at 15.8 times sales despite declining revenue. Rivian, meanwhile, trades at just 3.7 times sales, while Lucid shares trade at roughly 7.6 times sales. Why such a premium for Tesla stock? The likely reason is Tesla's ability to pursue huge growth opportunities like robotaxis, even if that growth remains hypothetical today.

For now, neither Lucid nor Rivian has any plans to operate a robotaxi service themselves. But Lucid does have a partnership with Uber Technologies to supply it with 20,000 vehicles to power that company's robotaxi business. Rivian, meanwhile, has been fairly quiet about its robotaxi plans, though the company has invested heavily in autonomous driving features.

Will Rivian or Lucid become the next Tesla?

When it comes to mimicking Tesla's rise, the two keys seem to be the production of low-cost vehicles and the ability to pursue massive growth opportunities like robotaxis. Rivian has a lead in the former category, while Lucid seemingly has a lead in the latter category. From an investment standpoint, which is the better stock today? Rivian looks like the winner here.

Don't get me wrong: Lucid's exposure to the robotaxi market is exciting. But the company is simply a supplier, not an operator. It has far less to gain than robotaxi operators like Tesla or Uber. The company also skipped a step in Tesla's master growth plan: Getting affordable vehicles to market.

This is where Rivian has a heavy lead. The company should have affordable vehicles on the roads by early 2026. Management has been very clear that the production schedule remains on track. Lucid, however, has provided far fewer details. Its relatively smaller access to capital, meanwhile, could hinder its ability to scale production.

With Rivian shares trading at a 50% discount to Lucid on a price-to-sales basis, I'm sticking with the cheaper stock that has a more defined growth path in the year to come.