Yes! The specifics depend on whether you're using a hosted Wordpress blog at wordpress.com.
If you're using the self-hosted version (wordpress.org), then you should be able to use all of the standard chat snippets. You can paste your chat snippet embed code into an HTML Widget or Text Widget and add that Widget to your site.
If you want to use embed chat boxes using the simple iframe method, you will probably need to install something like the Wordpress sidebar IFRAME widget.
Here is an example of a wordpress.com blog using the above approach. In this example, an image of a chat box is used as the thing that the user clicks on to launch the real chat box.