The CW may have to rethink some of its strategy when it comes to "Vampire Diaries."

Following a less-than-spectacular second season premiere, the series starring Nina Dobrev, Paul Wesley and Ian Somerhalder fell from its already lower-than-expected opening last week, losing 5 percent of its audience to finish Thursday with a 1.9 rating/3 share.

Usually, a 5 percent drop is nothing to worry about. But compounding the problem is the fact that the new series "Nikita," which serves as a lead-out from "Vampire Diaries," is actually staying ahead. It earned a 2.1/4, according to Fast National overnight ratings from The Nielsen Co., once again finishing ahead of "Vampire Diaries." That's just a 4.5 percent audience drop -- much smaller than many followup weeks to a series premiere.

"Nikita" is now more than 10 percent better than "Supernatural" was in the same timeslot in its second week last season, and the show's 2.2/4 average is 29 percent better than "Supernatural's" total season average in the timeslot.

"Vampire Diaries," on the other hand, is averaging a 2.0/3 this season, 13 percent off its average from last year.

The two shows continue to be the best-rated on The CW so far in this young season, however. "Vampire Diaries" is deadlocked with "America's Next Top Model" for the No. 2 spot in the network's lineup behind "Nikita," which are both well ahead of "Hellcats," "90210" and "One Tree Hill."

The CW will finish the week with a 1.6/3, down 20 percent from its premiere week which only included four shows.

Fast Nationals usually provide a snapshot of what Americans are watching by pulling numbers from the top urban markets that include both live viewing and same-day timeshifted viewing. A rating point generally represents more than 1.1 million households while the share indicates the percentage of televisions turned on that was tuned to the specific program. These numbers typically shift when final ratings are issued.

Data collected from The Nielsen Co., as distributed by Zap2it. BlipNetwork tracks non-news, non-event programming, and figures for this story reflect airing of new episodes only. For more information on the Audience Loyalty Index, click here.