NEW YORK — Fox News Channel is being taken to task for an ad in which it claims to be the “No. 1 network for political coverage.”

The news cabler failed to get Nielsen Media Research approval before using its info. Now Nielsen is reviewing the data to see whether the ad is inaccurate or misleading.

On Tuesday, spokesman Jack Loftus said: “They have an agreement with us that if they’re going to run advertisements using our data, they will submit them to us first for approval. They did not do that.”

Nielsen has a similar agreement with all its clients.

It’s not unusual for nets to put the most positive spin on numbers, but some rival webs think FNC may have gone too far.

“The ad is wrong,” Turner spokesman Robert Romano said. “Throughout the year, viewers have been turning to CNN for their political and election coverage.”

The ad, which ran in various trade papers and daily newspapers, claims that FNC airs the No. 1 political program, newscast on cable, primetime cable news program, debate program and news program at 10 p.m. It also says that “6.8 million viewers watched FNC’s election night coverage,” which includes people who were tuned into the Fox broadcast network, which simulcast FNC’s election coverage.

CNN wins vote

During primetime on Election Night, CNN averaged 5.82 million viewers, followed by MSNBC with 2.96 million viewers. FNC trailed behind with 2.41 million viewers.

FNC’s “ads are ironic, especially since they have ranked No. 3 for the last five days during the biggest story of the year,” said MSNBC spokesman Mark O’Connor.

According to the fine print at the bottom of the ad, the source is Nielsen’s October 2000 numbers, which means that election coverage isn’t included as “political coverage.”

Fox News was not available for comment.

CNN tops election ratings

Meanwhile, the never-ending presidential election race helped fuel all of the cable news nets last week, driving CNN to the top spot among all basic cable nets in primetime ratings.

During primetime, CNN posted an average of 2.46 million viewers, compared with MSNBC’s 1.18 million viewers and Fox News Channel’s 1.12 million viewers, according to Nielsen numbers for the week of Nov. 6-12.

In total day, CNN garnered 1.4 million total viewers, while MSNBC posted 705,000 total viewers and FNC trailed with 614,000 total viewers.

CNN’s total day and primetime averages for the week were up sharply from the third quarter, with gains of 367% in ratings and 340% in total viewers during primetime.