Sens. Ron WydenRon WydenMnuchin aiming for tax reform by August Dems rip Trump administration for revoking Obama's transgender directive IPAB’s Medicare cuts will threaten seniors’ access to care MORE (D-Ore.) and Lisa MurkowskiLisa MurkowskiGOP governors confront Medicaid divide GOP senator won't vote to defund Planned Parenthood A guide to the committees: Senate MORE (R-Alaska) are poised to unveil legislation to reform the country’s much-maligned campaign finance rules.

The lawmakers announced a Tuesday news conference to release the bill, which seeks to counter an influx of unregulated political spending that followed the U.S. Supreme Court’s 2010 Citizen’s United ruling. The decision paved the way for unlimited outside spending on political races.

As a result, the 2012 election was the costliest in American history, with spending on federal races totaling roughly $6 billion, according to the Center for Responsive Politics. 

In late December, Wyden and Murkowski announced they had agreed upon a framework for legislation that would reduce the “anonymous sleaze and innuendo” that characterized the last election cycle, they wrote in an opinion editorial published in The Washington Post.

“The anonymity of much of this spending encourages ads that lower the level of political discourse and makes it harder, not easier, for Americans to make informed decisions,” they wrote.

Under their plan, groups involved in political activity – whether directly through a campaign or via outside advocacy – would be required to disclose their donors in real time.

“Under federal law, which requires only quarterly reports, the influx of money immediately before an election is hidden from the public until months after the votes have been counted,” the lawmakers wrote.

The bill draws on state laws already enacted in Oregon and Alaska. It would be applicable to all federal candidates and “every billionaire hoping to influence an election,” they said. The laws would also apply equally to corporations, nonprofits and labor unions.

“Unlimited corporate and individual spending is corrosive to democracy and undermines the political process,” Widen and Murkowski wrote. “But the case has been decided, and it is our prerogative as legislators to improve on it.”