The Obama administration just wrapped up another big year for regulations and executive actions -- pushing through everything from a new type of retirement account to a deportation reprieve affecting millions of illegal immigrants to long-awaited standards for coal waste.
But thousands of proposed regulations remain on the table and could set the stage for a rush of rulemaking in the president's final two years in office.
Some of the biggest items are expected from the Environmental Protection Agency, which is set to finalize several landmark rules in 2015. Perhaps the most controversial concern new regulations on coal-fired power plants.
The Obama administration is trying to get fossil-fuel fired power plants to reduce carbon dioxide emissions by 30 percent from 2005 levels by 2030.
The EPA proposed the rules last year and is set to finalize them by summer 2015.
But with Republicans taking control of the Senate and boosting their numbers in the House, incoming leaders are girding for battle.
Incoming Senate Majority Leader Mitch McConnell, a Republican who represents the coal state of Kentucky, told The Associated Press last month he'll do all he can to stop regulations hurting the industry.
Though the administration is pushing the regulations as part of a broad plan to improve air quality and curb global warming, McConnell told the AP: "My first obligation is to protect my people, who are hurting as the result of what this administration is doing."
He added: "I'm going to do any and everything I can to stop it."
According to the Competitive Enterprise Institute, the Obama administration put out 2,375 proposed rules in 2014 that are still under consideration. That's in addition to 3,541 final rules and regulations in 2014, according to CEI.
The sheer number of rules from the Obama administration is not unprecedented. Early in the George W. Bush administration, the annual number of rules topped 4,000. But critics say this administration is imposing more expensive regulations.
Among them is a controversial EPA proposal to expand regulatory power over streams and wetlands. The agency, set to finalize the rule in April, estimates it could impose costs of between $162 million to $278 million per year, but says "public benefits outweigh the costs" -- since, the EPA says, the changes would reduce flooding, support hunting and fishing, and ease pollution.
Republicans, though, have described the maneuver as a massive land grab.
The plan would define which specific waterways the EPA can regulate. The Clean Water Act already gives the EPA the ability to regulate "U.S. waters," but Supreme Court rulings have left the specifics unclear when it comes to waters that flow only part of the year.
The EPA claims this does not expand its authority, and only clarifies it.
But detractors claim it is an opening for the EPA to claim authority over countless waterways, including streams that only show up during heavy rainfall. Critics warn this could create more red tape for property owners and businesses if they happen to have even small streams on their land.
Rep. Lamar Smith, R-Texas, chairman of the House Science, Space, and Technology Committee, has called it an effort to "control a huge amount of private property across the country."
In another EPA initiative, the agency is looking to October to finalize sweeping ozone regulations.
In proposing the limits on smog-forming pollution linked to asthma and respiratory illness in November, EPA Administrator Gina McCarthy argued that the public health benefits far outweigh the costs and that most of the U.S. can meet the tougher standards without doing anything new.
"We need to be smart -- as we always have -- in trying to find the best benefits in a way that will continue to grow the economy," McCarthy said. Of reducing ozone, she added: "We've done it before, and we're on track to do it again."
But business groups panned the proposal as unnecessary and the costliest in history, warning it could jeopardize a resurgence in American manufacturing.
President Obama initially had pulled the EPA's proposed ozone limits amid intense pressure from industry and the GOP. But public health groups sued, and a federal court ordered the EPA to issue a new draft smog rule by last month -- which the agency did.
The rules are estimated to cost industry anywhere between $3.9 billion and $15 billion by 2025. That price tag would exceed that of any previous environmental regulation in the U.S. Environmental groups are pushing for stricter limits still.
On other fronts, the Federal Communications Commission could move in a matter of months to propose new "net neutrality" rules. Obama weighed in on that debate late last year, urging the FCC to regulate the Internet like other utilities.
The White House is calling for an "explicit ban" on deals between broadband Internet providers and online services like Netflix, Amazon or YouTube to move their content faster, a potential new source of revenue for cable companies. While the FCC is an independent agency, Obama's statement could put political pressure on FCC commissioners.
Meanwhile, the National Labor Relations Board has issued new rules for so-called "ambush" union elections -- speeding up elections and requiring employers to give unions contact information for workers. The rules take effect in April.
The Associated Press contributed to this report.