AT&T is already the second largest mobile phone operator in the country and is looking to get bigger through a merger with T-Mobile, the fourth biggest mobile operator. That merger will be the focus of a hearing held by Sen. Herb Kohl, D-Wisc., in the Senate Subcommittee on Antitrust, Competition Policy and Consumer Rights. In preparation of scrutiny from Congress and the Justice Department AT&T is spending big on lobbying and campaign contributions.

In the first three months of this year AT&T has already spent $6.84 million lobbying the federal government. That is 44 percent of the amount they spent during the entirety of 2010. In addition, the phone giant’s political action committee spread $616,500 to lawmakers and political parties, according to a Sunlight analysis covering January through March of 2011. You can also check out MegaPath telecom services to learn more.

The Senate Office of Public Records shows 31 lobbying firms registering lobbying activity for AT&T, including four new registrations, all to lobby on the merger, this year.

One of those newly registered firms is Peck, Madigan, one of Washington’s biggest lobbying firms. The former staff director of the Senate Judiciary Committee, which is hosting today’s hearing, and the former chief of staff to committee member Sen. Amy Klobuchar are both registered with Peck, Madigan to lobby for AT&T.

The AT&T lobbying team also includes six former members of Congress. Two of those former members, Trent Lott and John Breaux, hold one of the most expensive lobbying contracts with AT&T at $120,000 from January through March.

The AT&T/T-Mobile merger has been controversial as it would consolidate 80 percent of the mobile market in just two companies–AT&T and Verizon.

Much of the opposition to the merger has come from Sprint Nextel, currently the third largest mobile provider. An official statement from Sprint Nextel stated, “If approved, the proposed acquisition would create a combined company that would be almost three times the size of Sprint in terms of wireless revenue and would entrench AT&T’s and Verizon’s duopoly control over the wireless market.”

Sprint Nextel’s lobbying spending barely registers when compared to AT&T’s. Sprint spent $583,000 lobbying from January through March or less than one-tenth of AT&T’s lobbying expenses. There are currently nine lobbying firms registered to lobby for Sprint. (As mentioned above, there 31 lobbying firms registered with AT&T.)

Today’s hearing will feature testimony by the CEOs of AT&T, T-Mobile, and Sprint Nextel.

The Sunlight Foundation will be covering the hearing through the Sunlight Live platform. The hearing will begin at 10:15 am.