A blog post on Wall Street Journal site reports that AT&T is working on an ad campaign to convince regulators and lawmakers on the merits of its proposed takeover of T-Mobile (News - Alert) USA. The blogger Shira Ovide wrote that the telecom giant is planning to launch an advertising drive in the Capital to sell the original point that the T-Mobile deal is better wireless service.

“In case you’re wondering why Sprint (News - Alert) is trying to kill the AT&T/T-Mobile merger… It’s all about spectrum,” reads the text of the AT&T ad slated to run starting Tuesday in publications popular on the  Capitol Hill, such as the Washington Post, Politico and the Hill newspapers, wrote Ovide. However, according to the blogger, AT&T (News - Alert) declined to disclose how much it is spending on the ads.

As per the blogger, the marketing pitch is part of AT&T’s two-track effort to push through its $39 billion acquisition of T-Mobile, despite opposition from the U.S. Department of Justice. Meanwhile, AT&T’s first meeting with Department of Justice is on Wednesday. And the wireless operator hopes to reach a negotiated deal with the regulators that can pave the way to a completed deal, wrote Ovide.

In another ad, AT&T says “We have a plan to combine our limited spectrum with T-Mobile to create a 4G LTE (News - Alert) mobile broadband network that will reach 97 percent of Americans.”

The WSJ blog indicates that T-Mobile deal could improve AT&T’s cache of wireless spectrum, the government-leased airwaves that carry cell phones calls and wireless Internet data. With surge in mobile Internet data traffic, wireless capacity is becoming a bottleneck for wireless operators and more spectrum and bandwidth is needed to overcome this problem.

AT&T rival Sprint, which has filed a lawsuit to block the T-Mobile acquisition, has said the deal will “create a clear wireless duopoly that could raise prices, stifle innovation and cost American jobs,” wrote Ovide.