If lines forming at electric-car maker Tesla Motors' (NASDAQ:TSLA) stores around the world today are any indication of how well the company's newest vehicle will sell, it looks like Model 3 could be a hit. Of course, there's one big caveat: None of these customers making reservations have actually seen the vehicle. That won't happen until tonight.

Model 3 event art. Image source: Tesla Motors.

Tesla hopes the Model 3, which will have a starting price of $35,000, will play a key role in driving sales growth for the company. So, many investors may be looking to initial demand as a window into whether the company's expectations for its lower-cost car are realistic.

Model 3 mania
Beginning in Australia, it was quickly clear the turnout for in-store Model 3 reservations wouldn't disappoint. Significant lines had formed at Tesla's Australia stores before they opened on Thursday to begin accepting reservations. And the mania at most U.S. Tesla stores appears to be even greater this morning.

Observing Tesla's Denver, Colorado location, there were over 400 people in line before the store opened -- a figure that appeared fairly commonplace at Tesla stores across U.S. locations.

A range of videos and photos on Twitter and Instagram showing Model 3 lines highlight the large turnouts at Tesla stores:

At many locations, customers camped out in order to get the first spots in line. Colorado's Andrew Soeldner was one of these individuals.

Soeldner reserved the first Model 3 in Colorado. Image source: author.

"I'm incredibly proud and excited to be a part of what I think is the most important moment in transportation history in the last 100 years," Soeldner said.

This is Soeldner's first Tesla. He is upgrading from a 2003 Toyota Corolla, but he is expecting to purchase every available option for the vehicle.

When asked how he felt about not knowing what the vehicle looks like, he said, "Previous models have been striking. I have confidence in Franz von Holzhausen and his design team to hit another homerun."

"We've experienced hundreds of customers at nearly every Tesla store in North America," said a Tesla spokesperson to The Motley Fool on Thursday.

Online reservations begin tonight
While in-store reservations began this morning, customers will be able to put deposits down to reserve Model 3 online by later tonight.

Initially, Tesla was going to begin accepting online reservations for Model 3 when the unveiling started at 8:30 p.m., but Tesla CEO Elon Musk said on Twitter Thursday morning the company will now begin accepting reservations one hour before the event "to ensure no server overload."

Elon Musk high-fiving customers at a California store on Thursday morning. Photo by Teslarati, used with permission.

Musk appeared to be in good spirits Thursday morning and was seen at California stores handing out high-fives to customers.

"Incredibly inspired by the interest in Model 3," Musk said on Twitter Thursday morning. "You won't be disappointed."

The Model 3 shown tonight will only be a prototype. The company doesn't plan to begin deliveries of the vehicle until the end of 2017.

For those interested in tuning into the event, it will be streamed live at the company's website at 8:30 p.m. PT.

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