Yes. For example, see this: http://www.dnjonline.com/article.aspx?id=jun07_access3264
What's important to know: you cannot link 32-bit code and 64-bit directly, statically or dynamically.
In principle, you can even avoid using COM; in this case you can have two different processes, one would be 32-bit, another 64-bit. One such process can serve up others regardless their target platforms in the same manner of a library via remote procedure call (RPC) mechanism.