The Tesla Motors (TSLA 4.96%) naysayers are growing in number again. The latest exchange data shows that there were 25.4 million shares sold short as of mid-November. This is the highest short interest for the electric-car maker since the end of April.

It's easy to see why the boo birds are out. The stock has surrendered 36% of its value since peaking less than three months ago, bucking the general market that has moved on to hit fresh highs in that time. We've seen Model S fires gnaw away at its ballyhooed safety accolades. We've also seen stateside deliveries cool. Tesla counters that it's scaling back domestic shipments to satisfy European demand, but are waiting lists getting that much longer? 

One can argue that the shorts appear to be right given the stock's swift fall from grace, but that may be off the mark. When the stock peaked in late September there were just 20.9 million shorts. Many have been shorting the stock on the way down, just as they have historically been covering when the stock moves higher. 

Tesla's short interest peaked in mid-March at 32.3 million shares when the stock was at $35.29. We know how well that played out. Even with the swift drop in recent weeks -- and Tesla stock has closed lower in seven of the past nine weeks -- we're still looking at an investment that has more than tripled in that time. Shorts have a funny way of piling on at the wrong time here, and we may be seeing that again.

Tesla's shares opened sharply higher today after a German investigation into the Model S fires cleared the automaker.

The stock is certainly overvalued based on today's snapshot. You don't see automakers command $15 billion market caps -- or $24 billion at its September peak -- when they're on pace to only ring up $2.3 billion in revenue. However, Tesla's ability to crank out three consecutive quarters of adjusted profitability is a good omen for a model that's just starting to scale.

Tesla's potential for its pricey sedans may seem limited at the moment. There are established automakers selling just as many if not more plug-in cars than Tesla these days. However, between the Model X arrival late next year and the a more affordable model now a couple of years away it's hard to bet against Tesla's long-term potential.

You don't have to take my word for it. Check out the shorts. As long as they're rising history is on Tesla's side to rev up for another short squeeze.