What happened

Wall Street's unbridled love of electric vehicle stocks has waned, with investors getting a lot more choosy of late. Monday, however, was back to risk-on when it comes to the sector, with a handful of start-ups trading up big without any company-specific reasons.

Shares of Workhorse Group (WKHS -9.31%) and ChargePoint Holdings (CHPT -9.39%) were both up more than 10% as of 3 p.m. EDT, with shares of Churchill Capital Corp. IV (CCIV) up 7% and Nikola (NKLA -2.02%) up more than 5%.

So what

These companies have different focuses, but they all revolve around the electrification of the automotive industry. Workhorse and Nikola are developing electric-powered trucks and ChargePoint is rolling out a network of charging stations. Churchill Capital, meanwhile, is a special purpose acquisition company (SPAC) preparing to merge with electric car maker Lucid Motors.

The Lucid Air in front of a mountain landscape.

Exterior shot of the forthcoming Lucid Air sedan. Image source: Lucid Motors.

All of these stocks are relatively new to the market, and all got an enthusiastic initial welcome. But some of that excitement has faded. Workhorse earlier this year missed out on a potential $6 billion deal to build a new fleet of delivery vehicles for the U.S. Postal Service. Nikola has been battling fraud charges that led it to separate from its founder.

The market, of late, seems to be taking a fresh look at some of these companies. ChargePoint's strong performance Monday follows an equally impressive showing last week fueled in part by a partnership with Mercedes. Churchill last week finalized the date it would close its deal with Lucid, adding to investor confidence the deal will get done. And Workhorse is appealing the Postal Service decision, giving investors at least some hope the outcome might be reversed.

Even hard-hit Nikola is plugging along, working toward its goal to develop sources of "clean" hydrogen gas. On Monday, at least, enthusiasm about the potential for these businesses is outweighing concerns from critics.

Now what

The bulls are in charge today with these names, but investors should remain cautious. We are still in the early days of the electric vehicle revolution and a lot can go wrong. None of these companies have in any way secured their place among the winners once the shakeout is over.

Of the four Lucid would be my preferred choice, with a clear business plan and the funding to execute thanks to its pending merger with Churchill. Workhorse's appeal still seems like a long shot, with perhaps just a small slice of the order its best possible outcome. Nikola has a lot of work to do to establish itself as a credible business, and ChargePoint is battling to be a part of what could be a quickly commoditized market.

Be it Lucid or any of these others, any investor looking to buy in should limit these names to a small part of a well-diversified portfolio.