In general, yes, you can - under a process known as "Automatic Revalidation".
In short, Automatic Revalidation allows your existing visit to the US to continue if you have left the US to a neighboring country (ie, Canada or Mexico) and returned - even if your visa is no longer valid (which in effect, yours isn't as you've used your single allowed entry).
There are some specific conditions to using this process, and you should check the relevant pages on both the US State Department and the US CBP websites to confirm you're allowed.
Given the recent removal of I94 forms, I would suggest printing out a copy of your current I94 from the website http://www.cbp.gov/i94 before leaving the US, as well a printing out a copy of the document above from the US CBP website just in case you have any problems when checking in for your flight from Canada to the US.
Obviously depending on your nationality you may also require a visa for Canada.