E-Vote uses the web2py framework and can be installed like any other web2py application; see the web2py documentation for details. If you just want to try out E-Vote quickly, here is one way to get it up and running on your laptop:
$ git clone --recursive https://github.com/web2py/web2py.git
$ cd web2py/applications
$ git clone https://github.com/mdipierro/evote.git
$ cd ..
$ sudo /etc/init.d/apachectl stop # <-- stop other web server if needed
$ python web2py.py
...Watch it launch, then visit
http://127.0.0.1:8000/evote/default/index
...in your browser.
To deploy at the root of the site (e.g., at http://127.0.0.1:8000/ instead of http://127.0.0.1:8000/evote/default/index), simply name the E-Vote directory applications/init/ instead of applications/evote/. The magic name "init" will cause E-Vote to appear at the site root.
To deploy E-Vote in production, you may want to go to web2py.com and learn more about deploying web2py-based applications in general. If you're in a hurry, see scripts/setup-*.sh in the web2py tree. One common way to deploy web2py applications is with WSGI under Apache HTTPD: in the web2py tree, copy handlers/wsgihandler.py to the top level of the tree, and set the appropriate WSGI options in the Apache configuration. See the Deployment recipes chapter in the web2py manual for more.