As the D.C. Council met for its weekly breakfast this morning, one of the topics on members’ minds was Uber, the upscale livery service, and an amendment proposed by Mary Cheh (D-Ward 3) that would have made Uber compliant with D.C. regulations by implementing a price floor.

Uber was such a hot topic at the breakfast table not because of its turbulent history with the D.C. Taxicab Commission, but because the company, in a span of about 18 hours, marshaled its loyal customer base to mount a forceful email, social media and telephone campaign opposing Cheh’s measure.

Several councilmembers mentioned that their offices had received upward of 5,000 emails about Uber since about 4 p.m. Monday, when CEO Travis Kalanick sent out a mass email and blog post denouncing the amendment and urging Uber’s fans to contact the Council.

A spokesman for Councilmember Jack Evans (D-Ward 2), told DCist that Evans’ office received more than 4,000 emails. David Meadows, spokesman for Michael A. Brown (I-At Large), said the number his office received was “no less than 5,000.”

Several Council offices equated the viral campaign with ones previously mounted for hot-button social issues. “More lobbying than same-sex marriage,” Meadows said.

Cheh’s office, unsurprisingly, was one of the most heavily targeted. A senior aide in her office reported receiving 3,768 emails about Uber, along with several hundred phone calls.

“It was extreme,” the aide said. “When we have these big email campaigns it’s a lot of cut and paste. But there were a lot of people who wrote their own thoughts, and that’s impressive.”

Still, considering the differing accounts between Cheh’s office and Uber about the crafting of the amendment—the councilmember said they negotiated “in good faith” while Kalanick refuted that—Cheh’s staffers said they found themselves having to confront frustrated Uber customers who did not have the complete picture.

“I spoke to them, and every single person but one, when I walked them through, they said ‘oh,’ ” the aide said. “The information [Kalanick] put out there was not at all accurate.”

Councilmember David Catania (I-At Large) also reported receiving between 5,000 and 6,000 emails about Uber in the past day, while a spokesman for Jim Graham (D-Ward 1) said his office received about 3,000 messages, many of which were filtered through a petition listed on the activist website Change.org. The Change.org petition garnered thousands of signatures and was cited by Uber supporters from the District, the suburbs and states halfway across the U.S., Graham’s spokesman said.

Uber’s intense lobbying effort extended to social networking, too. Beyond the tens of thousands of emails they sent to D.C. Council members, Uber’s wired customers sent a constant stream of Twitter messages in support of the company, usually marked with the hashtag “#UberDClove.”

And while Uber’s campaign found success in getting Cheh to shelve her amendment to a sweeping taxicab modernization bill that has been in the works for several months, her office maintains its measure was in the livery service’s best interest

“We like Uber,” the senior Cheh aide said. “We said from the beginning we like Uber. I understand [Kalanick] believes it’s legal and that we were trying to ensure that they were.”

In D.C., Uber’s social media operation is conducted by Alex Priest, who frequently engages with the company’s customers over Twitter. Priest did not reply to inquiries from DCist.

Additional reporting by Martin Austermuhle