As the third quarter winds down, all eyes are on Tesla's (TSLA) - Get Report delivery figures.

The electric carmaker is expected to release its latest delivery figures sometime next week, and it'll be the next big test for the stock. One clue as to what the number will be was provided by a leaked memo CEO Elon Musk sent to employees, which was published by the Tesla fan site Electrek, in which Musk wrote that he believes that Tesla "has a shot" at delivering 100,000 cars in the third quarter.

Tesla shares were up 5.9% to $242.21 on Thursday afternoon on the news, although they're down more than 20% year to date.

"The challenge is making sure that we have the right car variants in the right locations and rallying as much as our company resources as possible to help with the end of the quarter deliveries," Musk wrote in the memo. 

Others are not quite so optimistic. 

In a note on Thursday, Wedbush analyst Dan Ives wrote that Tesla quarterly deliveries falling between 95,000 to 100,000 is an "unlikely event." 

"Based on the U.S. demand and improved European trajectory, coupled by pockets of weakness in China, we believe Tesla will come up shy of Street expectations with an 88k to 90k range more likely," Ives wrote, reiterating a neutral rating and $220 price target on the stock.

Tesla has been ramping up deliveries to Europe over the past several months, but demand in the U.S. is a source of concern for investors amid a drawdown of federal EV tax credits and more competitors preparing to enter the market. 

In its second quarter letter to shareholders, Tesla reported 95,356 vehicle deliveries overall and 77,634 deliveries of the Model 3, and reiterated its prior guidance of 360,000 to 400,000 vehicle deliveries for 2019. Tesla is "well positioned to continue growing total production and deliveries in Q3," the company wrote In July. 

Whether Tesla can meet Wall Street's delivery targets may come down to a last-minute delivery scramble this week. 

Ives estimated that there are between 5,000 and 7,000 vehicles in transit through Europe as of Thursday morning, which could be a make or break factor in Tesla meeting delivery targets for the quarter. On average, analysts anticipate 98,000 deliveries for the third quarter. 

Tesla is expected to report its third quarter earnings on Oct. 23, at which time investors will hear more about Tesla's elusive profitability goals as well as the demand picture going forward -- two ongoing concerns that have dragged down shares this year. 

Tesla "must steer through near-term headwinds around demand and profitability which remains the albatross around Fremont's neck," Ives added. 

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