It depends how promising your company is. That's the high bit of whether you can get funding, not your immigration status.

On the other hand, when investors think your company is unpromising, it's easier to say that the problem is your immigration status.

But don't kid yourselves that being in your home country will help your company either. Look at the startups that have succeeded so far. The empirical evidence says there's no advantage to being in a cheap labor market.