Tens of thousands of workers whose employers give them federal tax benefits for taking mass-transit to work could see their costs increase by about $1,000 a year because of congressional inaction.

U.S. Sen. Richard Blumenthal, D-Conn., was joined by New Haven Mayor Toni N. Harp, transit advocates and environmental leaders on Monday in pushing for a reinstatement of benefits that dropped sharply at the start of the year.

Blumenthal noted that the same shortfall occurred last year, but Congress was quick to reinstate the full program, which operates like a health savings plan for more than half of the state's 115,000 daily railroad commuters and about 2.7 million nationwide.

"Failure to extend this tax benefit will harm working families and small businesses, as well as clog the roads, contaminate our air, raise gasoline usage, cost consumers, and impose unfair discrimination against mass transit users," Blumenthal said in a statement.

At the start of the New Year, the amount of money commuters are allowed to set aside before taxes for public transportation fell to $130 a month, from $245.

"The expiration of the Commuter Mass Transit benefit will cost some public transit users up to $1,000 in additional costs," Blumenthal said. "By contrast, commuters who drive to work will be eligible to put away $250 month before taxes, up from $245 in 2013, for parking fees.

"Commuters from every corner of the state have expressed to me, through letters, emails and phone calls in recent months, how useful and important this benefit is to them on a daily basis," he said. "Commuters face an unconscionable double whammy -- higher fares, and an effective tax increase, unless we do the right thing and renew the full $245 benefit."

Blumenthal is a co-sponsor of the Commuter Benefits Equity Act, which would extend the commuter mass transit benefit through 2014.

Darien resident Jim Cameron, a commuter advocate who joined Blumenthal and Harp in a news conference in New Haven's Union Station, recalled that last year Congress restored the full benefit retroactively for the rail commuters.

He estimated that as many as 75,000 of the state's rail riders have employers that participate in the federal tax benefit program.

"We just had a 5 percent fare increase," Cameron said in a phone interview. "So now it costs $458 a month from New Haven to New York and $300-plus from Stamford. I am hearing anecdotally from commuters that it's not worth living in Connecticut. I am concerned that the cost of being a commuter in Connecticut is becoming increasingly expensive."

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