Only if they release both WiiU and NX versions at the same time. It's going to be difficult surpass Twilight Princess without that double release
If it's a double release than it's possible. But there's no way they're selling over 8 million copies just on the WiiU.
Have some time to kill? Read my shitty games blog. http://www.pixlbit.com/blogs/586/gigantor21