As they try to break the impasse holding up the lobbying and ethics overhaul, House and Senate leaders are planning to rewrite one of the most controversial portions of the measure.

The two chambers approved different versions of the key provision — requiring for the first time that lobbyists report campaign checks they bundle for candidates — when they passed reform packages earlier this year. But now, Senate Democratic leaders are redrafting the reform to shift responsibility for the disclosure from lobbyists to the candidates themselves, several sources close to the process confirmed.

The change would have the effect of giving lawmakers control over the sensitive disclosure. Depending on how the new language is written, it also could weaken what reform advocates hailed as one of the most significant accomplishments in the overhaul packages.

Democratic leaders on both sides of the Capitol are scrambling to wrap up work on the reform bill — a key campaign pledge from 2006 — before heading home for the August recess. So far, they have been stymied from heading to conference negotiations by an objection from Sen. Jim DeMint (R-S.C.), who is demanding the Senate adopt earmark transparency rules internally rather than leaving them vulnerable to changes in conference.

With DeMint showing no sign of budging, Democratic leaders have devised an end-run around the conference process that calls for rewriting the bill, pushing it through the House and then bringing it to the Senate floor in a manner that blocks any amendments. The substance of the measures largely would remain the same, those close to the process said, with the significant exception of the bundling disclosure rules.

Aides said they hope to have the rewrite finished by the end of the week so the bill can come to a vote next week.

The bundling disclosure proposals met widespread resistance in both chambers earlier this year. In the House, unease over the reform among a number of veteran lawmakers stalled progress on the package for months and nearly sunk it when it came up for a vote in May.

Rep. Chris Van Hollen (D-Md.), who crafted the House version of the provision, said he and other House leaders are still undecided on moving the reform from the lobbying disclosure books to campaign finance statutes. He said they are waiting to see details of what Senate leaders come up with.

“As long as you have the same information captured, I think it’s a wash,” he said. “It’s not a disagreement. We’re at the ‘show-me’ stage. Show us how you’d do it.”

Reform advocates are wary. Last week, when word of the proposed change began to circulate, six leading groups rallying behind the ethics overhaul sent a letter to Speaker Nancy Pelosi (D-Calif.) and Senate Majority Leader Harry Reid (D-Nev.) saying they “adamantly oppose” the move.

They argued the change would disperse information the original bills would have centralized in lobbying disclosure reports, making it harder for average citizens to access it.

Since then, however, officials with the groups have backed off a bit in favor of a wait-and-see approach.

“We’ve got some well-earned skepticism here, but how this is written will really determine if its effective disclosure,” said Meredith McGehee, policy director at the Campaign Legal Center.

While Democrats craft the final package, Senate Republicans — including Minority Leader Mitch McConnell (R-Ky.) — have complained this week that they have been shut out of the negotiations.

For instance, McConnell on Tuesday told reporters he had not yet been given details of the ethics package and was not being involved in the talks.

“As you know, there’s not a conference and Republicans are not, as far as I know … allowed to participate in the process. I’m hopeful. You know, this bill started off at the beginning of the year on pretty strong bipartisan footing. It was a Reid-McConnell bill in the Senate. But since we are not in conference, I really couldn’t tell you” what’s happening, McConnell said prior to the GOP Conference’s weekly luncheon.

Additionally, 10 reform-minded Republicans — including presidential hopeful Sens. John McCain (Ariz.) and Sam Brownback (Kan.), as well as DeMint — wrote to Reid on July 20 expressing their support for the Senate package and concern that it will be changed during the closed talks with House Democrats.

“While we will reserve final judgment until we have an opportunity to review any new legislation that you may propose, please know that we strongly believe that any related legislation brought to the Senate floor must be at least as meaningful as the reforms provided for” in the Senate bill, the lawmakers wrote, adding that they “urge [Reid] to reconsider reported plans to curtail members’ rights to fully debate and amend a new bill if it is weaker than the bill supported by you and 95 other members last January.”

Aides to McConnell have been briefed on the issue by Reid’s aides, although at press time it was unclear how detailed those talks were.

A McConnell spokesman said the GOP lawmaker had not made any requests for changes to the bill, noting that he has not been included in the talks.

Ironically, one GOP leadership aide said DeMint’s demands that earmark reforms in the bill be adopted prior to the conference ultimately may have led Reid and Pelosi to lock out Republicans entirely.

Instead of having a “1 percent chance” of amending the bill during conference, DeMint’s complaints — while “perfectly legitimate,” the aide said — have put Republicans in a situation in which the bill is being written by Democratic leadership. It’s “negotiated by a conference of two: Harry Reid and Nancy Pelosi. … There’s a zero percent chance [now] that we’ll get what we want” in the bill, the aide said.

The aide also predicted DeMint and his fellow reformers will find it difficult to rally enough votes to block the bill if they are unhappy with it.

“It’s going to be a hard bill to swat down” because of the public interest in ethics reform, the aide said.

Sen. Tom Coburn (R-Okla.), one of DeMint’s closest allies, agreed. He said that at this point, many Republicans appear unwilling to take the politically risky move of blocking the ethics package, even if it is a weaker version.

“Everyone’s afraid to vote against it because they’re afraid of looking like they’re voting against ethics reform,” Coburn said, adding, “The question is, ‘Do you really want to fix this problem or do you just want to look like you’re fixing the problem?’ This bill doesn’t fix the problem.”

Although GOP leaders have been careful to not rule out a filibuster, they have indicated they are hopeful a bill will pass before August, and privately Republicans said McConnell and others have made it clear they are not in the mood for a bloody fight with Democrats on ethics in the runup to the August recess. Additionally, while conservatives have been careful to lay the blame for their unhappiness at the feet of Reid over the past week, Republicans acknowledged a lack of leadership support has rankled some feathers among reformers.

“For our leadership to vote against earmark reform and be AWOL on this debate is no way to win back the majority,” one conservative staffer complained.