Most people who drive frequently have experienced that chilling sensation when an eighteen-wheeler starts drifting over the lane markers and looms like a moving mountain above them. Fortunately, the truck driver usually corrects the drift—often after some frantic honking of the horn and wild gesturing from a panicked commuter.

Drifting trucks are most likely the result of driver fatigue. Truck drivers these days are notorious for long hauls and short breaks, but that wasn’t always the case.

Back in 1979, truck drivers averaged today’s equivalent of $101,600 in yearly wages. Today, the average is a little over $52,000. Pay has dropped so much that drivers find themselves putting in extra miles to make ends meet, but those extra miles mean fewer breaks and more driver fatigue, which can lead to more accidents and danger on the road.

Driver fatigue could probably be countered with more breaks for drivers, but politicians like Jeff Denham are doing everything they can to make sure drivers who take breaks are penalized. Denham and fellow Republicans want to prohibit states like California from requiring paid rest and meal breaks for truck drivers.

Denham’s opposition to breaks for truck drivers isn’t surprising; he’s a top recipient of campaign contributions from the trucking industry and he serves on the House of Representatives Transportation Committee.

But truckers aren’t the only workers punished by Jeff Denham’s allegiance to big donors; working women also get the shaft. In 2016, Jeff Denham opposed the Paycheck Fairness Act, which would have narrowed or eliminated the gender pay gap; at that time it was at 84%, with California women receiving 16% less pay than men for the same work.

Jeff Denham’s general opposition to fair wages is likely most evident in his failure to achieve immigration reform. The U.S. Department of Labor estimates 46% of farm labor is performed by undocumented immigrants, who routinely work for lower pay than citizens.

Though Congressman Denham has promised to achieve immigration reform every election year, he never has and almost certainly never will, because his loyalty is to big donors like Stewart Resnick, who want to keep farm labor prices at a minimum. He’s not just opposed to minimum wage increases, he’s also fought against overtime pay for farmworkers, whose median annual income is barely above $14,000.

All in all, most American workers have gone backwards in income over the last forty years, despite working more hours per year than people in most other developed countries, even including the hard-working Japanese. Yes, that’s right. Americans work more hours per year than the Japanese, but in terms of income relative to inflation, too many American workers have lost ground.

The reasons aren’t hard to fathom. Politicians like Jeff Denham have greater allegiance to corporate donors than to working Americans—it’s that simple.