In October last year, Chitika conducted a survey that revealed that the iPhone 5 was ahead of the Samsung Galaxy S III in terms of Web usage. Now, four months later, or as Chitika puts it, “many weeks removed from the holiday season, and as the winter months come to a close,” is Apple’s top-line smartphone still leading Samsung’s?

The answer, according to a new study performed by the third-party analytics company, is yes … but just barely.

To quantify the study, Chitika sampled millions of mobile ad impressions originating from all types of Apple iPhones and Samsung smartphones on the Chitika Ad Network. This data set was composed of impressions in the U.S. and Canada from Feb. 1 to Feb. 9, 2013.

Comparing the specific usage rates for the iPhone 5 and the Samsung Galaxy S III, Chitika has found that, as mentioned, the former is slightly ahead of the latter. Take a look at the graph above.

Whereas the iPhone 5 held as much as a 12 percent point lead over the Samsung Galaxy S III in the previous survey, Apple’s flagship phone now leads Samsung by only two percent points.

As Chitika succinctly sums it up, “the amount of Web traffic generated by Samsung Galaxy S III and iPhone 5 users is a near-50/50 split.”

Chitika has also generated the graph below to show how the two handsets fare within the larger context of the smartphone market in North America.

North American Web Traffic Share by Mobile Phone Chitika

Chitika notes that …

… the data points to iPhone 5 and Samsung Galaxy S III users generating a combined 13% of all smartphone Web traffic in North America. Users of both companies’ smartphones as a whole generate a substantial 62.1% of overall continental smartphone Web traffic. However, this is a 1% drop from our October study, indicating there has been some more diversification, rather than uniformity, within the smartphone marketplace over the past four months. This is particularly true in regards to Apple, which held a 46% share of smartphone Web traffic in October, but has seen that share drop to 41.5% as of February, 2013. Meanwhile, Samsung’s share of smartphone traffic has grown from 17% to 20.6%.

Just a couple of days before this study, Chitika reported that Apple’s iOS 6 is now running on over 80 percent of iDevices.