Robyn Blumner, columnist for the St. Petersburg Times, has an excellent column on liberals, campaign finance regulation, and free speech:
Why don’t liberals understand the freedom-crushing nature of campaign finance reform?
How come it is easy for liberals to see the First Amendment interest in other overheated free speech issues, such as reporting on the classified operations of the National Security Agency or displaying Robert Mapplethorpe nudes, but when it comes to political discourse during an election season, they’re all for government restraints.
This is the same question that famed First Amendment lawyer Floyd Abrams raises in his autobiographical book Speaking Freely: Trials of the First Amendment. In one chapter, Abrams recounts a speech he gave to a Unitarian church congregation in New York City in 2000. The audience was very friendly toward his discussion of the Pentagon Papers case and the Brooklyn Museum case in which Abrams defended the museum after then-New York Mayor Rudolph Giuliani sought to cut its funding. The mayor had been deeply offended by a Nigerian artist’s use of elephant dung in a painting of the Virgin Mary that the museum exhibited.
But when Abrams said that the McCain-Feingold campaign finance reform measure would likely put unconstitutional limits on political activity and promote censorship of political speech, his audience audibly objected.
The only thing I would add to Blumner's analysis is that conservatives have been totally complicitous in the adoption of campaign finance regulation and the erosion of free speech. John McCain, for example, is the co-sponsor of the 2002 Bipartisan Campaign Reform Act. More generally, conservatives as well as liberals recognize that campaign finance regulation protect the jobs of incumbent politicians, so they happily sign on.