During their long campaign to loosen rules on campaign money, conservatives argued that there was a simpler way to prevent corruption: transparency. Get rid of limits on contributions and spending, they said, but make sure voters know where the money is coming from. Today, with those fundraising restrictions largely removed, many conservatives have changed their tune. They now say disclosure could be an enemy of free speech. High-profile donors could face bullying and harassment from liberals out to “muzzle” their opponents, Sen. Minority Leader Mitch McConnell, R-Ky., said in a recent speech. Corporations could be subject to boycotts and pickets, warned the Wall Street Journal editorial page this spring. Democrats “want to intimidate people into not giving to these conservative efforts,” said Republican strategist Karl Rove on Fox News. “I think it’s shameful.” Rove helped found American Crossroads, a “super PAC,” and Crossroads GPS, a nonprofit group that does not reveal its donors. “Disclosure is the one area where (conservatives) haven’t won,” said Richard Briffault, an election law professor at Columbia Law School. “This is the next frontier for them.”