Shares of Tesla Motors Inc. gained Wednesday after a Goldman Sachs analyst raised urged investors to buy shares of the electric car maker ahead of the delivery of its new Model S sedans.

THE SPARK: Analyst Patrick Archambault increased the six-month price target on Tesla shares by 39 percent, to $50 from $36, and backed his "Buy" rating.

THE BIG PICTURE: Tesla, co-founded by PayPal billionaire Elon Musk, has only sold a few thousand sports cars in its nine-year history. The Roadster has a limited market because of its $109,000 price tag.

The company will start delivering what it hopes will be a mass-market vehicle, the Model S sedan, on Friday. The sedan starts at $49,900, after a tax credit. Tesla expects to sell 5,000 sedans this year.

THE ANALYSIS: Archambault said that if the Model S sells well, investors will be more optimistic about upcoming models and the company's future.

Tesla has never been profitable, with a deficit of $759 million from its founding through the end of March. The market for electric cars remains small in the U.S., with little infrastructure for charging autos.

The company has said it expects to be profitable in 2013.

SHARE ACTION: Tesla's stock gained $1.81, or 5.6 percent, to $33.90 in midday trading. Shares had gained 12 percent in 2012.

Tesla's initial public stock offering priced at $17 two years ago.