AT&T's year-to-year spending on lobbying has been up for the first and second quarters of 2011, but regulators are still eyeing its proposed acquisition of T-Mobile with suspicion.

Facing increased regulatory scrutiny for its proposed acquisition of T-Mobile, AT&T has been pushing its message to Congress via more lobbying than the company has previously conducted.

According to the company's latest quarterly disclosure report, AT&T spent $4.9 million to lobby the federal government in the second quarter of 2011. That's an increase of 58 percent from the amount spent during the same time period last year, $3.1 million. While it's a brief drop from AT&T's $6.8 million spending on lobbying during the first quarter of the year, that figure is itself a 15 percent increase from the company's first quarter lobbying spending in 2010.

In other words, AT&T is really taking to the congressional airwaves in 2011.

To be fair, however, the company isn't just chatting up Congress and other government agencies about T-Mobile-related matters. AT&T's topics of conversation also included lobbying in support of proposals that would free up more wireless spectrum for the company to use for its various mobile broadband services, including mobile apps and online video.

AT&T has also lobbied on measures to support the creation of a national wireless broadband networkbased on a 10 Mhz, $3 billion chunk of 700 MHz commercial wireless spectrum known as the "D Block"that would allow emergency personnel priority access to the spectrum during emergencies. Draft legislation related to the matter is currently calling for an auction of the D Block instead of a exclusive allocation of the spectrum to public safety agencies.

It's not just AT&T that's shouldering the lobbying burden in its attempts to better its T-Mobile pitch. The company's partner in the process, T-Mobile, spent a total of $1 million in the second quarter of 2011 in support of the proposed acquisition as well as wireless spectrum-related proposals. That's a 66 percent increase from the amount of money the company used to lobby Congress and related agencies in the second quarter of 2010, and a 44 percent increase from the $690,000 the company spent in the first quarter of 2011.

With the Senate's top antitrust lawmaker recently coming down on the proposed acquisition "highly dangerous to competition and consumers"perhaps AT&T and T-Mobile will need to sink a few more dollars into the lobbying pot if they're going to have any shot at boosting the image of the $39 billion deal in front of the federal agencies that could block it.

For more from David, follow him on Twitter @TheDavidMurphy.