At a time when it seems like only bad news is coming out of Washington, the U.S. Senate scored one for the environment on Wednesday.

Power plants are the largest source of mercury pollution, which harms humans and wildlife alike. By a vote of 53-46, the Senate on Wednesday rejected a Tea Party-led initiative that would have allowed dirty power plants to avoid pollution controls on mercury. Both New York Senators, Chuck Schumer and Kirsten Gillibrand, helped defeat the measure. 

The bill, introduced by longtime environmental foe Sen. Jim Inhofe, would have rolled back the the Mercury and Air Toxic Standards Rule -- a centerpiece of the Obama administration's environmental record. That rule requires coal- and oil-fired power plants to install and operate "maximum achievable control technology," or MACT, by 2015 to prevent 90% of the sector's mercury emissions.

The rule also reduces several other air toxins, and stems from provisions under the 1990 Clean Air Act.

Half the country's energy companies already have strapped on the necessary pollution equipment without economic hardship, said Senate Environment and Public Works Committee Chairwoman Barbara Boxer, Democrat-California.