Merging Client/Server Side Templating Engines

I'm about to start a new project using node, backbone, underscore, and express among other things. On the views side I am using jade. I know I am going to have tons of ajax like interactions so I was going to use handlebars; however, I feel that there would be a significant amount of code duplication from my jade templates.

Is there a way to render the jade templates and fill in data straight from client side? How can I route requests directly to the views without filling in the data?
If I can't do the above it seems that I actually have a few templating engines I could use, underscore, jquery, handlebars... Is it not a waste to have all of those templating engines laying around? Should I just use underscore or jquery and not even worry about handlebars any more? Is there a preferred engine?
Is there some hybrid method where I can fill in data similarly to handlebars into my jade templates?

javascript
templates
node.js
handlebars.js
underscore.js

Express isn't doing any magic with jade template rendering. Simply have a look at the public api and you know how to render jade views on the client side. For routing requests on the client side you can use page.js from the express author. A little bit of work and magic and you have routes working with the exact same code on the server and client side and both are rendering to jade.