Electric automaker Tesla Motors said Wednesday it would seek to raise $1.4 billion to $1.7 billion in a stock offering to fund the production of its mass-market electric car and accelerate its production expansion. The company said it would use the funds to ramp up production of the Model 3, its first model aimed at the mass market, which CEO Elon Musk has said will begin in late 2017. The Model 3 represents a significant logistical, financial and technological hurdle for Tesla. But the company said in a public filing Wednesday that it is accelerating its plans to build 500,000 vehicles annually. Previously, it projected it couldn't sell that number until 2020. Now, it says it plans to hit the target by 2018.