Sales continue to rise for the little electric car that could. General Motors (NYSE:GM) said that it sold 2,781 examples of its Chevrolet Bolt EV in the U.S. in October. 

It was the Bolt's best month for sales since its launch last December.  In fact, it was so good that it appears that the Bolt out-sold mighty Tesla (NASDAQ:TSLA) in the U.S. in October.

A black Chevrolet Bolt EV, a small hatchback, parked with mountains in the background.

Sales of General Motors' all-electric Chevrolet Bolt EV hit an all-time high in October. Image source: General Motors.

Yes, the Bolt out-sold Tesla in the U.S. last month

First, about that Tesla point. InsideEVs tracks the number of plug-in vehicles sold in the United States every month. Their figures for Tesla are estimates -- alone among automakers, Tesla reports sales numbers quarterly rather than monthly -- but they've proven to be pretty accurate over time. 

InsideEVs estimates that Tesla delivered 1,120 Model S sedans, 850 Model X SUVs, and 145 Model 3s in the U.S. in October, a total of 1,970 -- 666 short of the Bolt's October U.S. sales total. 

Assuming that InsideEV's numbers are roughly accurate, that's a first for the Bolt. Aside from bragging rights (if GM chooses to brag), it probably doesn't mean a whole lot. But it's a milestone that's worth noting. 

Bolt sales have risen steadily since February

Here's a look at how Bolt sales have risen since its launch last December.

A bar chart showing monthly U.S. sales of the Chevrolet Bolt EV rising from 579 in December of 2016 to 2,781 in October 2017.

Data source: General Motors' U.S. sales reports. Chart shows U.S. sales of the Chevrolet Bolt EV by month since its introduction in December of 2016.

Until recently, it was easy to say that the Bolt's rising sales were driven mostly by increasing supply, not rising demand. The only GM dealers certified to sell the Bolt in its first few months on the market were in California and Oregon. GM added dealers in 19 other states over the course of the spring, and finally allowed dealers nationwide to order the Bolt starting in June.

Because it typically takes several weeks for cars ordered by a dealer to arrive, the Bolt wasn't really available nationwide until August. Sales are still rising, thanks in part to some advertising. But it's still hard to be sure we're seeing the true level of demand, as GM may not be able to increase production very much from here for a while yet. 

GM has said that its production of Bolts is "on plan," meaning that it's building Bolts at the pace it expected as of the beginning of 2017. But it has been reported that GM's plan was to ramp up to a pace of about 30,000 Bolts a year, or about 2,500 a month. If so, GM and (critically) its suppliers may need some time to increase production significantly from the current pace. 

GM probably won't be able to keep up with Tesla for long

Tesla, of course, is scrambling to ramp up production of its new Model 3. While it has once again missed its optimistic production forecasts, it's clear that at some point, it'll be building lots of Model 3s. At least as of right now, it appears that GM isn't set up to keep pace. (That said, GM has more electric vehicles in development, and the sales race will look a lot different in a year or two.) 

In fact, you'll note that GM sold more than 2,500 Bolts just in the U.S. last month. While Bolt sales have risen impressively since its launch, we may be near the peak: It may be hard for GM to supply enough Bolts for sales to rise much further, at least in the near term. 

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