The legislation is a top priority for state, county and local governments, added Brian Namey, a spokesman for the National Association of Counties. "There are champions in the House and Senate who are working to make this happen," he said by email. "We can't just sit here and let the year come to an end after coming so far."
If Congress does not pass the legislation by the end of the year, supporters would have to start over with a new bill in 2015.
In addition to the rally in Washington, D.C., supporters are running television commercials calling on Congress to pass the sales tax bill.
"Every night in America, hundreds of small businesses close their doors forever" because of a lack of an Internet sales tax, one commercial says.
The online sales tax "loophole" will give Chinese e-commerce service Alibaba an unfair advantage over U.S. businesses, a second commercial says. "This Chinese company will decimate our local retailers," the commercial says. "Unless Congress ends special tax treatment for Alibaba and other online giants, Main Street will never look the same."
Opponents of the bill say a new sales tax would be difficult and costly for Internet sellers to comply with. Some opponents have objected to what they see as a new tax, despite current requirements for Internet shoppers to report their purchases.
Backers of an Internet sales tax "have spent a fortune" pushing for the sales tax bill, said Steve DelBianco, executive director of NetChoice, an e-commerce trade group. "They aren't surrendering until this Congress adjourns."
Backers of the bill are trying to tack it on to other important legislation, but congressional leaders have been stripping controversial items out of legislation during this end-of-the year session of Congress, DelBianco said. "Nobody believes that MFA could pass on its own," he said
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