If Democrats win the keys to the governors’ mansions in several states today, they could defy President Trump by adopting California’s stricter tailpipe pollution rules for cars.

Thirty-six states are set to elect governors today, and 23 of those seats are currently held by Republicans (E&E Daily, Nov. 5).

If Democrats prevail in a handful of states—including Illinois and New Mexico—they could look to thwart the Trump administration’s rollback of Obama-era clean car standards. Their magic weapon would be a special provision of a landmark environmental law.

At issue is Section 209 of the Clean Air Act, which gives California the authority to set tougher greenhouse gas emissions standards for light-duty vehicles than the federal government. Congress handed the Golden State that authority in the 1970s due to its unique air pollution problems and smoggy skies.

Under Section 177 of the Clean Air Act, other states can choose to adopt California’s tougher rules. Thirteen states and the District of Columbia have done so, representing about 40 percent of all new cars sold in the United States. Colorado is set to soon become the 14th.

It’s the prerogative of governors to decide whether to join California. That means a Democratic governor could override a Republican attorney general in the same state. Colorado offers an illustrative example of this dynamic.

In June, Colorado Gov. John Hickenlooper (D) announced that he would sign an executive order to adopt California’s stricter car rules (Climatewire, June 19). Hickenlooper didn’t coordinate the move with state Attorney General Cynthia Coffman, a Republican.

Coffman, for her part, didn’t join a May lawsuit against the Trump administration over its push to loosen the car rules (E&E News PM, May 1).

Hickenlooper is due to retire, and observers expect him to mount a presidential bid in 2020. In the meantime, Democratic Rep. Jared Polis and Republican State Treasurer Walker Stapleton are fiercely contesting his open seat.

Regardless of the outcome, though, state regulators have already taken steps to implement Hickenlooper’s executive order. Colorado’s Air Quality Control Commission voted in August to open a rulemaking process to consider adopting California’s car rules (Greenwire, Aug. 17).

There are two big reasons that newly elected Democratic governors could choose to adopt California’s stricter car rules. One is to defy the Trump administration, which has proposed freezing fuel economy standards at 2020 levels through 2026 and revoking California’s Clean Air Act waiver. The other is to ensure compliance with the federal National Ambient Air Quality Standards (NAAQS).

The states that have already adopted California’s car rules are New Jersey, Connecticut, Washington, Vermont, New York, Maine, Rhode Island, Massachusetts, Oregon, Pennsylvania, Maryland and Delaware.

Janet McCabe, acting EPA air chief under President Obama, said those states rely on the stricter car rules to meet the NAAQS for ozone and other criteria pollutants.

“When states do their air pollution plans, they use assumptions about what the air quality is going to be in future years based on the regulations that are in place,” McCabe said. “Motor vehicles are such a huge proportion of local air pollution, and states since 2012 have been using projections of future emissions from motor vehicles based on the clean car rules.”

While McCabe wouldn’t speculate about specific candidates, she said she would welcome additions to the ranks of states that have joined California.

“I can certainly weigh in that it would be welcome news for additional states to decide that they want to protect their citizens from air pollution and they want to contribute to lowering their states’ carbon footprint,” said McCabe, who is now a senior law fellow at the Midwest-based Environmental Law & Policy Center.

Here’s a look at two gubernatorial races where a GOP-held seat could flip to a Democrat opposing Trump’s rollback of clean car rules:

Illinois

Democrat J.B. Pritzker hopes to unseat incumbent Republican Gov. Bruce Rauner in Illinois, a reliably blue stronghold that Democratic candidate Hillary Clinton carried in the 2016 presidential election.

Pritzker, a venture capital investor and heir to the Hyatt Hotels fortune, has already broken the national record for a self-financing candidate, the Chicago Sun-Times reported.

He hopes to galvanize Democrats and moderates upset with Trump’s divisive rhetoric and environmental rule rollbacks. If elected, he has promised to join an alliance of states committed to upholding the Paris Agreement and to set the state on a path toward 100 percent clean energy.

Pritzker has attacked Rauner for not doing enough to thwart the Trump administration’s deregulatory agenda.

“Bruce Rauner has been silent as Donald Trump wages war on our environment,” he says on his website. “While leaders of cities and states across the country stepped forward to say that they will continue to uphold the provisions of the Paris agreement, Bruce Rauner failed to act.”

If Illinois adopted the stricter car rules, it would help with air pollution problems in the Greater Chicagoland area.

In 2015, EPA tightened the ground-level ozone standard from 75 parts per billion to 70 ppb. But the entire Chicago area has been in nonattainment for both the 2008 and 2015 thresholds, according to the EPA Green Book.

The Cook Political Report rates the race as “likely blue.”

New Mexico

Democratic Rep. Michelle Lujan Grisham faces another member of Congress, Republican Rep. Steve Pearce, in an increasingly purple state.

Lujan Grisham has emerged as an environmental favorite. She has called for making New Mexico a leader in clean energy and for implementing a statewide policy to curb methane emissions from oil and gas wells.

Lujan Grisham has called for state leadership on climate policy in the absence of strong federal action and has put in a plug for electric vehicles.

“I will work to ensure that our residents can enjoy the lower operating costs, higher fuel efficiency rates and lower carbon emissions of electric cars,” she states. “We will encourage greater energy efficiency in New Mexico’s transportation sector, adopting enhanced emissions standards and working to create the infrastructure for widespread adoption of electric vehicles in New Mexico.”

In an interview with the New Mexico Political Report, Lujan Grisham also signaled that she looks up to Hickenlooper, the first governor to adopt the tougher car rules after the Trump administration unveiled its rollback.

Asked how she would balance environmental concerns with those of the oil and gas industry, Lujan Grisham said, “I like to quote Gov. Hickenlooper, who talks about how New Mexico ceded its leadership on environmental issues and concerns with oil and gas. ... I do believe we gave up our leadership position in that regard, and I intend to take it back and show Hickenlooper we can do it even better than Colorado.”

The Cook Political Report rates the race as “leaning blue.”

Reporter Sean Reilly contributed.

Reprinted from Climatewire with permission from E&E News. E&E provides daily coverage of essential energy and environmental news at www.eenews.net.