Former Giffords aide Gabe Zimmerman, who was killed in January 2011. (AP)

A Capitol Hill conference room named for an aide to former Rep. Gabrielle Giffords (D-Ariz.) who was killed in a January 2011 shooting will be formally dedicated next week and the former lawmaker is expected to attend the ceremony, organizers said.

The House voted in 2011 to name a large basement conference room in the Capitol Visitors Center used frequently by House Democrats for Gabe Zimmerman, 30, who served as Giffords’s community outreach director. He had organized the constituent event at a Tucson supermarket where Giffords and others were shot. In addition to Zimmerman, five others were killed, including federal judge John Roll and 9-year-old Christina Taylor Green.

Organizers said Giffords and her husband, Mark Kelly, are expected to attend the dedication Tuesday, as will Rep. Ron Barber (D-Ariz.), who was wounded in the Tucson shooting and later succeeded his former boss.

The timing of the dedication ceremony coincides with ongoing debate in the U.S. Senate over a new bill designed to curb gun violence that is supported by Giffords and others survivors of the shooting.

In hopes of compelling the Senate to act quickly, Giffords used Twitter Monday to ask: “What are we waiting for? I can’t remember a time when this many Americans spoke with such a united voice in favor of anything.”

Follow Ed O'Keefe on Twitter: @edatpost