Some of our users complained about the log in button being at the bottom of the ideas categories list on the left side of an ideas portal. We had several cases, where users have not find the log in button in the first place (and with this also the "edit profile" button) and wondered why they were not able to see all ideas (as a majority of them are private on a public ideas portal in our case).
Our organization recently went through an email domain change and this also led to several cases where users didn't just change their email address, but accidentally registered again with their new email address, which created a second account for the same user.
My suggestion is to position the log in button somewhere at the top of the page. I guess most of the users are used to that from other websites.