The Hill reported that the telecom giant has sponsored at least 14 events and receptions, shows a list compiled by Quinn Gillespie & Associates, a lobbying firm that received $60,000 in the second quarter of this year to represent the company.

Among other events, AT&T has hosted a party for the House Democratic Blue Dog Coalition featuring pop star KT Tunstall and special lunch receptions for the Maryland, Illinois and California delegations.

Campaign finance watchdogs say AT&T is trying to influence political leaders.

"They wouldn't be paying for all of this if they weren't getting good return on their investment -- visibility which translates into access and influence," said Meredith McGehee of the Campaign Legal Center.

For its part, AT&T said it's being a good corporate citizen, noting that it also will host events at the Republican National Convention in Minneapolis next month.

"Additionally, the presidential conventions give AT&T a unique opportunity to present and display the many leading-edge technologies and innovations that we offer to tens of thousands of consumers," a company statement said. "That's why we contribute and participate."