If traveling by CAR to Canada will I need a passport after the 1st of the year?

I live in Ohio, and I was curious if after the first of the year if traveling by car if I would need a passport to get into Canada?

I have read if you were to FLY there you would, but what about driving?

Thanks in advance.
I will be traveling with my husband and son to MarineLand . Incase anyone is wondering.

the US have defered this until june of 2009

No, you won't need one. Just photo i.d.

Just so you know, Marineland is closed until May. Your description sounded like you may be coming early in the new year.