Liberal advocacy group Fed Up launched a campaign nearly three years ago in hopes of persuading the nation's central bank to hold off raising its benchmark interest rate.

The group organized protests at the Fed's annual retreat in Jackson Hole, Wyoming. It demonstrated outside the Federal Reserve Bank of New York. And it recruited prestigious economists and former top central bank officials to the cause.

But now, Fed Up has a new target: Republicans who want to curtail the central bank's power.

House Financial Services Chairman Jeb Hensarling, R-Texas, is expected to introduce legislation soon that would require the Fed to set rules for conducting monetary policy and explain any deviation from those rules. The Fed has bristled at the proposal, arguing that the proposal limits its power to revive the economy in moments of crisis.

Fed Up agrees, finding common ground between itself and the central bank it was created to criticize. The group mobilized its members at Fed Chair Janet Yellen's appearance Tuesday before the Senate Banking Committee. The group held protests ahead of her semi-annual testimony and intends to pack the hearing room with members wearing bright green shirts bearing slogans such as, "Whose Recovery?" Executive Director Shawn Sebastian said Fed Up met with several senators before the hearing to voice its concerns.

"We see the [bill] as speeding us toward another financial crash and preventing the Fed's ability to respond to another financial crash," Sebastian said.

The so-called Financial Choice Act would also roll back some of the regulatory authority handed to the Fed following the 2008 financial crisis. Sebastian said his group would be closely watching President Donald Trump's nominees to fill the three vacant seats at the central bank's board of governors in Washington. Fed Up has pushed for greater diversity among Fed appointees, both on the board and among the 12 regional central bank presidents.

The alliance could provide the Fed with its own grassroots support as it attempts to steer clear of the populist anger against economic elites that helped propel Trump into the White House. The president has promised to "do a number" on the post-financial crisis reforms known as the Dodd-Frank Act that were designed to, among other things, curtail risky behavior among banks and protect consumers from unscrupulous practices by lenders.

A draft version of Hensarling's bill includes shifting the Fed's annual bank stress tests into two-year cycles and changing the way banks calculate risk, among other things, according to a memo obtained by CNBC.

"Donald Trump and [Treasury Secretary] Steven Mnuchin, the foreclosure king, don't care about stories like mine. They only care about their billionaire friends," Philadelphia resident Tyrone Ferguson said in a prepared speech. "Now Trump and his billionaire friends want to take over the Fed, too."

Fed Up has proven adept at navigating the often esoteric world of central banking. The group has met with Yellen and Vice Chairman Stanley Fischer. It also raised pointed questions about racial diversity and ties to Wall Street during a discussion with top central bank officials at the Jackson Hole conference last year.

Sebastian compared the Fed's 14-year appointments to those of the Supreme Court. He said he will continue to press the central bank on those issues — as well as the lawmakers responsible for confirming the Fed's new governors.

"The entire world has shifted around us," Sebastian said. "But our principles have remained the same on this."

By Ylan Mui            

Source