I think so, but it depends on "big". You probably can get to $20-50 million without much in the way of sales. They did have reasonable marketing.

It's when they started targeting the mass market, getting funding, removing features their early adopters loved (eg. wiki syntax in Confluence) that they needed a sales force. But that was necessary for their plan to scale. They're still not huge ($600 million is excellent but not Red Hat).