Chevrolet's two plug-in cars with the similar names - the Volt and Bolt - got off to tepid sales starts this year, with the Bolt doing comparatively better.

General Motors reported 1,177 Bolt EVs sold in January, a mild 1.3-percent increase over last year's 1,162, whereas the Volt EREV saw 713 deliveries, a 55.7-percent decline over January 2017's 1,611.

The Bolt's number, while up, also comes against the fact that it is now nationally available, and a year ago at this time it was not, but still early in its schedule of rolling out to the nation. Sales of the 238-mile range electric car had started in Oregon and California in December 2016, and so, its availability was less. A 1.3-percent year-over-year increase therefore is not a super-sized uptick.

By contrast, the Volt, which was nationally available a year ago is purely down. It also finished 2017 a bit behind the Bolt with 20,349 sales to the Bolt's 23,297. The Bolt was the second-best selling plug-in car in the U.S. behind an estimated 26,500 deliveries of the Tesla Model S. The Volt placed fifth behind the Tesla Model S, Bolt, Tesla Model X, and Prius Prime.

What lies ahead this year for the two cars saleswise is an open question.

Their slow starts in a historically slow sales month are not necessarily any real indicator, but a lower-priced all-new Nissan Leaf, potentially Tesla's Model 3 which is still supposed to increase production to fill a big backlog, and other cars will also vie for mindshare.

Green car analyst Alan Baum is not projecting more than 25,000 for either one, but as is always true, no one actually knows the future.