This question requires EU seeing as how there's only been one Hutt in all of the 6 movies (not counting Jaba's entourage in TPM).
I think the hutts could pull it off. By themselves they could weild blasters. Their girth indicates they'd probably be able to take some damage before being taken out. They'd probably utilize vehicles of some kind, whether they be fast moving ones or huge siege weapons and tanks. Then past that they'd be able to put a lot of money out for mercs. If Jaba's palace is any indication to how Hutts lived it seems Hutts already have small armies of followers that they'd command.
The hutts could be a force to be reckoned with.
EU necessary for Thread Question to be answered; Activating Anti-Contradiction programming from Queeq not closing thread once this became apparent.
Pre-Republic days saw a Hutt empire of sorts following their victory over Xim. In the Old Republic days, there was a large enough standing Army combined with the Jedi to keep the Hutts in line, military-wise. As of the post-Ruusan era, the Republic was already so big and bloated from a corrupt bureaucracy that it would have been too expensive time consuming and unnecessary to maintain such a force that could truly be called an "army." Then the Empire comes around and by no means would the Hutts dare tango with the biggest military build up in known history. Then you have the collapse of Jabba's reign and the Black Sun resulting in feuding Hutts and other crime syndicates competing for what's left. Then you get the failed Darksaber project, a tentative agreement with New Republic officials, a power vacuum arising from the Empire's slow decay (numerous War Lords tearing things up, the New Republic taking control, Thrawn, the Empire Reborn, Palpatine returning.) Throw in the Yuuzhan Vong invasion, and the entire post-ROTJ era makes for poor recruitment in a Hutt army.
Yada yada yada, there's an answer to the thread. It's EU, Queeq, kill this.