WASHINGTON (AP) — California’s congressional delegation will take a double hit when a new Congress convenes in January.

Its two Democratic senators will be serving in the minority for the first time since 2006, while the House delegation will have lost more than a century of legislative experience after a handful of Democrats and Republicans decided to retire.

Chief among the losses, Democrat Henry Waxman is retiring after 20 terms. Colleague Nancy Pelosi said Waxman made his mark challenging sacred cows, most memorably the tobacco industry, where his work led to stronger health warnings on cigarettes and gave the U.S. Food and Drug Administration regulatory authority over tobacco products.

He also tangled with the pharmaceutical industry, spearheading efforts in the House during the 1980s to make it easier for generic drugs to enter the market.

“You name it: The bigger they were, the harder he fought,” Pelosi said.

Waxman, as chairman of the House Committee on Energy and Commerce, helped Democrats push through President Barack Obama’s health-insurance overhaul in 2010.  He also led the Democratic effort in the House to pass a bill meant to curb climate change, which the Senate declined to consider.

A fellow Democrat, Rep. George Miller, also is retiring after serving 20 terms. He helped push portions of the Affordable Care Act through his committee, Education and the Workforce, as well. During the previous administration of President George W. Bush, Miller worked with Republicans to pass the No Child Left Behind education overhaul.

The law beefed up testing requirements and held schools more accountable for poor performance. He also was a player on environmental issues, authoring a bill in the 1990s that required more water from the federal Central Valley Project to go toward restoring fish and wildlife habitat.

“Whatever state they would be from or whatever time in history they would have served, they are absolute giants in the history of the Congress,” Pelosi said.

Conservatives have a different point of view about what California will be missing.

Grover Norquist, a national anti-tax advocate, said he felt ambivalence about Waxman and Miller leaving. With the GOP in control, they couldn’t act on their priorities, anyway.

His chief complaint about their work over the years was that whatever help they gave one group took from others in the form of higher taxes and fees.