Environmental Protection Agency (EPA) Administrator Lisa Jackson will testify before the House Energy and Commerce Committee on Wednesday in what will be the first showdown between the newly empowered House Republicans and the EPA chief over the agency’s regulatory powers.

Jackson is no stranger to political battles, especially with those who are not as enthusiastic as she is about regulating greenhouse gas emissions or water and air pollutants. A December 2010 profile of Jackson in the Washington Post declared the administrator was “prepared for battle,” suggesting she doesn’t plan to back away from defending the EPA’s authority to regulate carbon, an authority that House Republicans reject.

Right before Republican Rep. Fred Upton of Michigan assumed the chairmanship of the Energy and Commerce Committee, he told reporters Jackson could reserve her own parking space outside the Rayburn House Office Building — suggesting the chairman would be calling Jackson to the Hill quite a bit to defend the agency’s actions.

“We’ll paint the curb yellow for them,” Upton said, referring to Jackson as well as Health and Human Services Secretary Kathleen Sebelius.

That animosity, however, hasn’t kept Jackson from becoming close with one of the fiercest climate change critics on the Hill – Republican Sen. James Inhofe of Oklahoma. Jackson even has a picture of Inhofe and his family framed and hung in her EPA office.

“Lisa is a very nice person, to start with,” Sen. Inhofe told The Daily Caller on Monday. “We don’t agree on anything philosophically, be she has always been fair.”

Here’s a look back at Jackson’s journey as a regulatory warrior.

She started in the New Jersey political system. Though Jackson officially began her career with a 16-year stint at the EPA, she was virtually unknown in national politics until then-New Jersey Democratic Gov. Jon Corzine nominated her to be Commissioner of Environmental Protection of New Jersey in 2006. There, Jackson spearheaded the state’s climate change plan to reduce greenhouse gas emissions to 1990 levels by 2020 and 80 percent below 2006 levels by 2050. Although her legacy at New Jersey’s Department of Environmental Protection (DEP) is mixed, Jackson is recognized for a relatively successful tenure.

For starters, Jackson was tough on climate change and clean water and air protections. She is responsible for giving more than 900 miles of waterways the highest level of protection under the Clean Water Act, which means development of said waterways was severely limited and buffer zones became a requirement.

Jackson was also instrumental in shaping a state plan that, among other things, called for a moratorium on new coal plants and for a requirement that after 2030, all new buildings have a net-zero energy consumption. During her tenure at the DEP, she was a strong proponent of cap and trade and was the vice president of the executive board of the Regional Greenhouse Gas Initiative – the organization responsible for pushing a northeastern regional cap and trade system.

“While running the New Jersey [DEP] she led the state’s effort to institute a regional cap and trade system that has since transformed into a state slush fund to fill New Jersey’s budget gap,” said Tom Borelli of the Free Enterprise Project.

The EPA’s endangerment finding.

After Jackson made it to the big leagues with Obama’s nomination in 2008 to head the EPA, she started things off with a hotly-contested endangerment finding. When the Supreme Court ruled in 2007 that the EPA could regulate greenhouse gas emissions under the Clean Air Act if the agency deemed the emissions posed a threat to public health, Jackson immediately went to work. And in 2009, the EPA released its endangerment finding, which ultimately became the basis of its defense in rolling out unprecedented regulations on carbon.

“This long-overdue finding cements 2009’s place in history as the year when the United States Government began seriously addressing the challenge of greenhouse gas pollution and seizing the opportunity of clean-energy reform,” said Jackson in a speech announcing the EPA’s finding. “In less than 11 months, we have done more to promote clean energy and prevent climate change than happened in the last eight years.”

Not everyone saw it that way, however. Republican lawmakers, in particular, saw the finding as a power grab and a backdoor attempt at implementing cap and trade after Congress failed to pass similar legislation. A senior adviser to Republican Sen. Richard Lugar of Indiana responded by saying Congress would probably find a way to “retaliate.”

“They could stop funding, and they could change the law,” the adviser said. Even the more liberal Republican Sen. Olympia Snowe of Maine called the EPA’s actions “regrettable.”

The subsequent lawsuits.

As a result of the EPA’s endangerment findings, at least 15 states and a host of other businesses and organizations are suing the agency. The U.S. Chamber of Commerce is among those organizations suing the agency. Their suit, however, is based on the process of the finding, while other groups contend the EPA didn’t spend enough time conducting research on the science of global warming. One of the fiercest lawsuits is being fought in Texas, where the state flat-out refused to issue permits for carbon emissions to its many oil refineries and coal-powered plants. The state won a small victory early last month when the U.S. Circuit Court of Appeals in D.C. blocked the EPA from stepping in and issuing the permits itself.

Jackson fights back.

Despite the anger she’s elicited on the Hill, Jackson has not backed down from defending the EPA’s power to regulate greenhouse gas emissions. After the 2010 midterm elections, Jackson said in an interview, “This agency is not the villain,” in response to attacks on new agency regulations. And just a month earlier, Jackson publicly fought back against industry criticism, while at the same time floating a future EPA-implemented cap and trade system. As a way to make the idea more palatable, she promised “as much as possible to give flexibility.”

“One of the most flexible programs we’ve ever had is a true cap and trade program,” Jackson said. “We can’t replicate that, but we can certainly look at opportunities.”

Just last week, Jackson told reporters that the Obama administration was committed to stopping legislation that would roll back the EPA’s efforts to regulate carbon. “What has been said from the White House is that the president’s advisers would advise him to veto any legislation that passed that would take away EPA’s greenhouse gas authority,” said Jackson. “Nothing has changed.”