Consumer-activist Ralph Nader formed a separate group last year devoted to helping Fannie Mae and Freddie Mac shareholders. (Jacquelyn Martin/AP)

Dozens of Fannie Mae and Freddie Mac shareholders flocked to Capitol Hill on Wednesday to rail against a Senate proposal that they say would trample on the rights of the mortgage giants’ investors, the latest in a frenzied push to influence the housing finance debate.

In the past two weeks, three groups have weighed in forcefully on the Senate legislation, which seeks to dismantle D.C.-based Fannie and McLean-based Freddie, replace them with a new entity and shift more of the risks of mortgage lending to the private sector.

These groups are demanding a stop to what they view as the government’s rip-off of Fannie and Freddie investors. In August 2012, about four years after the government took control of the two mortgage firms, federal officials directed the companies to turn over nearly all profits to the U.S. Treasury. Several investor groups have sued to challenge the arrangement.

The Senate legislation — by Tim Johnson (D-S.D.) and Mike Crapo (R-Idaho) — does not address how to deal with the shareholders. Some key lawmakers, including Crapo, have said they are looking to the courts for answers. But as a Senate panel prepares to vote on the Johnson-Crapo measure possibly later this month, the newly formed groups are making it known that they want Congress to deal with the issue.

On Wednesday, about 50 Fannie and Freddie shareholders went to Capitol Hill to deliver the message. Investors Unite, launched by Tennessee money manager Timothy J. Pagliara, organized the visit with support from consumer activist Ralph Nader, a vocal critic of the government’s treatment of the shareholders.

“This needs to be solved in Congress,” Pagliara, chief executive of CapWealth Advisors, said at a news conference to kick off the event. His firm’s clients own 8 million shares of Fannie and Freddie preferred stock. “It’s a cowardly act to throw that back at the court system.”

Shareholders responded with rowdy applause and waved signs that read “Shareholders Have Rights” and “Don’t Wipe Us Out.” Pagliara said the event was designed to highlight that the Fannie and Freddie debate affects 9-to-5 working people, not just monied hedge funds and institutional investors looking for a tidy profit.

Among the attendees were a Nevada homemaker, a Kansas farmer, a California human resources specialist and David Sims — a Seeking Alpha blogger in Richmond who helped organize the event by reaching out to other Fannie and Freddie shareholders on message boards.

Earlier this week, another group entered the fray. The Coalition for Mortgage Security announced its launch in a statement Monday and vowed to press for legislation that “responsibly winds down” Fannie and Freddie. But the Johnson-Crapo measure is not it, Ken Blackwell, the group’s director, said Wednesday.

The Senate proposal is “insufficient” when it comes to protecting homeowners, taxpayers and investors, said Blackwell, a Republican who has served as undersecretary at the Department of Housing and Urban Development and mayor of Cincinnati. His group plans to go national with its message via social media, traditional news outlets and town-hall meetings once its puts together a bipartisan team, Blackwell said.

“I personally don’t want the situation that we’ve had with Obamacare, where almost from the beginning, this is perceived to be a decisively partisan issue,” Blackwell said.

Another group, the conservative 60 Plus Association, invoked President Obama’s health-care law when it unleashed a $1.6 million blitz of television and radio advertisements targeting senators who support the Johnson-Crapo bill. The group bashed the bill for helping wipe out investor profits and urged senators not to “bring Obamacare to the mortgage industry.”

When the ads came out last week, supporters of the Johnson-Crapo measure, including the Consumer Federation of America and the Mortgage Bankers Association, said in a statement that 60 Plus was using “scare tactics.” 60 Plus, “along with hedge funds and other third party groups who have shown little other interest in housing, is offering misleading information and comparisons in an effort to derail this bipartisan reform effort that has been years in the making,” the statement said, adding that the hedge funds “could reap massive profits by keeping the housing finance system in its current state of limbo.”

It is unclear who is funding the campaigns of 60 Plus, the Coalition for Mortgage Security and Investors Unite because they are tax-exempt groups that are not required to disclose their donors. Through a spokesman, 60 Plus said it has 250,000 donors across the country who contribute to its efforts. Pagliara said he and other donors are funding his group and that many of the shareholders at Wednesday’s event on Capitol Hill paid for their trips to Washington.

The coalition headed by Blackwell said it will keep its supporters private unless they prefer to go public. “I don’t have any worries that we will be sufficiently funded,” he said.

But will all these groups have sway? Probably not, said Jaret Seiberg, an analyst with Guggenheim Securities. “I would say that any of these groups that pop up overnight to combat a single issue tend to have a lot less influence than established players who have been working with lawmakers through multiple election cycles,” Seiberg said.