Washington — Monday’s announcement by the Treasury Department that it will no longer collect information about donors to some political nonprofits was met with applause from Senate Majority Leader Mitch McConnell, perhaps the leading advocate for unrestricted campaign donations, even as it ignited a campaign finance fight in the middle of the 2018 midterm election.

“It’s bad enough to wield government power to chill political speech and invite harassment of citizens — based on what an angry mob might assume their opinions are, based on their private financial records,” the Kentucky Republican said on the Senate floor. “It’s even more egregious to pursue that nakedly political goal while calling it ‘good government.’ In this country, good government means protecting citizens’ First Amendment rights to participate in the competition of ideas — not trying to shut down that competition.”

For McConnell, campaign spending is key to his expansive interpretation of the First Amendment. Senate Democrats, led by Finance ranking member Ron Wyden, of Oregon, responded with criticism to the announcement.

Wyden said in a statement that he now would oppose President Donald Trump’s choice to head the IRS, Charles Rettig, unless there’s a commitment to rescind the new policy.

“Trump’s Treasury Department made it easier for anonymous foreign donors to funnel dark money into nonprofits the same day a Russian national linked to the NRA was arrested for attempting to influence our elections,” Wyden said. “It’s the latest attempt by Secretary (Steven) Mnuchin and Donald Trump to eliminate transparency and keep officials and lawmakers from following the money.”

The Finance panel is scheduled to mark up the Rettig nomination on this morning, the committee said on Monday.