While Nemesis was so bad that Maid in Manhattan beat it, I'm still convinced that The Two Towers played a role. It was such a huge juggernaut film released only 5 days after Nemesis. Naturally, Nemesis was over shadowed by it.
Of course, if Nemesis wasn't a train wreck it probably would have at least beat Maid in Manhattan opening weekend. Even then, The Two Towers would have demolished Nemesis when it opened a mere 5 days later.