Organizations which backed the voter-approved constitutional amendments guiding redistricting Friday blasted proposed maps slated to be voted on later in the day by the House Redistricting Committee.

In a 12-page letter to House Redistricting chief Will Weatherford, R-Wesley Chapel, former state Sen. Dan Gelber, a Miami Beach Democrat serving as legal counsel to Fair Districts supporters, effectively urged lawmakers to scrap the plans they’ve been working on.

The League of Women Voters, Common Cause and the National Council of La Raza have submitted an alternate approach to district maps that Weatherford today plans to introduce as an amendment to the House plan.

 The alternate proposal would “nest” three House districts within the 40-seat state Senate plan, making the boundaries more compact and logical for voters, Gelber said in his letter.

Congressional districts also would meander less, under the proposal. House, Senate and congressional maps recommended by the groups also would lean less Republican and prove more reflective of a state where registered voters are closely divided, with Democrats still holding a 500,000-voter edge.

“In sum, we believe that we have provided the committee with alternative proposals that comply with the Fair Districts amendments, while the proposals currently under consideration by the committee and those already passed by the Senate fail to comply with those amendments,” leaders of the organizations concluded in the letter to Weatherford.

The alternate maps likely stand little chance of being approved today.

But the letter lays out what could emerge as the central argument against the legislative maps when Florida’s redistricting effort advances for review to the state Supreme Court and U.S. Justice Department in coming weeks, and when Fair Districts advocate file an expected legal challenge.

The U.S. Supreme Court ruled today that corporations and unions can spend as much as they want on “electioneering communications,” the negative ads targeting candidates.

The ruling could have a sweeping effect on Florida campaigns, especially in battleground races like the U.S. Senate GOP primary between Gov. Charlie Crist and former House Speaker Marco Rubio.

The suit was filed by a group behind Hillary Clinton-bashing ads in her U.S. Senate campaign.

The court decided in Citizens United v. the Federal Election Commission that banning corporations and unions from paying for the ads equates to a chilling effect on free speech.

“There is no basis for the proposition that, in the political speech context, the government may impose restrictions on certain disfavored speakers. Both history and logic lead to this conclusion,” the ruling reads. “Political speech is so ingrained in this country’s culture that speakers find ways around campaign finance laws. Rapid changes in technology—and the creative dynamic inherent in the concept of free expression—counsel against upholding a law that restricts political speech in certain media or by certain speakers.”

Common Cause said the ruling “creates political crisis” by paving the way for corporations and unions to spend unlimited amounts of cash on elections.

“The Roberts court today made a bad situation worse,” Common Cause President Bob Edgar said in a press release. “This decision allows Wall Street to tap its vast corporate profits to drown out the voice of the public in our democracy. “The path from here is clear: Congress must free itself from Wall Street’s grip so Main Street can finally get a fair shake.We need to change the way America pays for elections. Passing the Fair Elections Now Act would give us the best Congress money can’t buy.”