Washington (CNN) - Senate Republicans narrowly blocked Democratic campaign finance disclosure legislation in the Senate Tuesday after raising concerns the bill would curb freedom of speech and tilt campaign spending in favor of the Democrats.
A 57-41 vote fell short of the 60 votes needed for the Senate to cut off debate on the measure. Republicans unanimously opposed the measure while Democrats solidly backed it.
Democrats said the legislation - known as the DISCLOSE Act - would bring greater transparency to campaign contributions from corporations, labor unions, and other special interests, which were able to ramp up political spending in the wake of the Supreme Court's controversial ruling in Citizens United vs. Federal Election Commission earlier this year.
The bill would require organizations paying for political advertising to disclose the names of their top donors in the ads, similar to what now is required of political candidates for federal office.
Republicans accused Democrats of trying to preserve their majorities in the House and Senate by skewing the rules in the favor of labor unions, trial lawyers, and other Democratic-leaning groups. Democrats denied that was their motive, and made certain changes to the bill last week aimed at satisfying GOP critics.
The Republicans were not mollified.
Updated: 5:06 p.m.