Alexa has a useful toolbar (will not work with Firefox though) which will give an actual visits ranking for websites, and what the trend has been.
An expert in this area, who showed me Alexa, said that if you start to get in the top 200,000 then that is getting some serious traffic. Recall there are several billion pages out there.
Out of interest I have looked up the ratings for the current week for the NZ party websites, and also over the last three months. The lower the number the better it is.
Labour – 479,000 this week, 1,283,000 at three months so increasing
National – 704,000 this week, 1,732,000 at three months so also increasing
NZ First – no ranking for this week, 1,252,000 at three months
ACT – 267,000 this week, 481,000 at three months so increasing
Greens – 1,095,000 this week, 806,000 at three months so slipping
United Future – no ranking for this week, 5,648,000 at three months
Progressive – no ranking