Canada's policy regarding felony convictions is very straight forward: "Anyone with a conviction in the United States that is treated as a felony or indictable offense in Canada is excludable from Canada, but even if the offense is not a felony or indictable offense in Canada, Customs and Immigration Officers have ultimate authority to permit and deny entry to Canada. ... Almost all convictions (including DUI, DWI, reckless driving, negligent driving, misdemeanor drug possession, all felonies, domestic violence (assault IV), shoplifting, theft, etc) can make a person inadmissible to Canada, regardless of when they occurred. For this reason, it is not recommended that persons with past convictions attempt to enter Canada without first obtaining necessary documents. It is always the final decision of officers at ports of entry to decide whether a person should be allowed into Canada." Traveling to Canada
You could apply for a waiver but that takes months and I don't believe you have the time to do so. You can apply to be admitted if you meet the following criteria: "Persons are eligible to apply for deemed rehabilitation at a port of entry if the following are true: There was only one conviction in total; At least ten years have elapsed since all of the sentences for the conviction were completed (payment of all fees, jail time completed, restitution paid, etc); The conviction would not be considered serious criminality in Canada (most felony convictions in the United States are equivalent to serious criminality in Canada); and The conviction did not involve any serious property damage, physical harm to any person, or any type of weapon."
I'm ex-US Customs. It's on a case-by-case basis.