Beacon Hill Democrats may be losing support from one of the party's most significant allies: organized labor, with at least one major union growing frustrated enough with legislative inaction to stop donating to most lawmakers. The electricians at IBEW Local 103, the ones with the big turbine off the expressway, are fed up with the Democrat-controlled Legislature's aversion to passing bills it says will help working people. Business manager Lou Antonellis said the union is returning the $200,000 dollars it would have given to lawmakers' political campaigns back to its members. "We're frustrated with business as usual, and, you know, our members work really hard for their money," Antonellis told WGBH News. "Their money is very valuable to them to spend it on Beacon Hill, where we're not getting much return on investment. It's probably better off in their pockets than it is in that investment." Union leaders Antonellis say the Legislature gave in to privatization efforts at t