The potential ethics pitfalls stemming from Donald Trump’s private enterprises will test congressional Democrats and government watchdog groups, as they try to pressure the incoming president to fully separate himself from his global business deals.

It is likely to be a long fight, spanning well into Trump’s presidency.

Kellyanne Conway, a Trump transition senior adviser, has said the president-elect is consulting with lawyers to ensure he is complying with ethics laws. Trump told The New York Times last week: “The law’s totally on my side. The president can’t have a conflict of interest.”

That has given little comfort to Democrats, in the minority in the House and Senate, who will have few official channels to make their case and to probe Trump’s administration for possible wrongdoing.

“The number of ethical violations and special interest entanglements make your head spin,” said Rep. John Sarbanes, an advocate for government ethics and a campaign finance overhaul.

The Maryland Democrat noted news reports that Trump met with foreign business executives amid his transition to power; included his daughter, Ivanka, who is helping run his business, in a meeting with Japanese Prime Minister Shinzo Abe; and encouraged foreign diplomats to stay in his hotels.

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“It’s breathtaking,” Sarbanes said. “Is the Oval Office just going to be another revenue center in the Trump business empire?”

Still, what Democrats can do is limited. Sarbanes said it will include “calling him out as these violations of ethical standards occur” and urging congressional Republicans to hold hearings.

Ethics watchdog organizations and academics with expertise in the issue say they, too, are urging lawmakers of both parties to conduct oversight and, in some cases, press for new legislation.

“This is a concern for all members of Congress, and they should put it at the top of the Republican agenda, to make sure President Trump, when he takes office, is conflict free and … does not subject him to the threat of scandal and the possibility of impeachment,” said Richard Painter, who served as an associate counsel to President George W. Bush. “There are just so many problems here.”

Though experts such as Painter, now a professor at the University of Minnesota Law School, agree that presidents are not subject to all the conflict of interest rules that govern their employees, they say presidents are not above bribery laws and the Emoluments Clause of the Constitution.

The clause forbids office holders, including presidents, from receiving any “present, emolument, office or title, of any kind whatever” from foreign governments. An emolument is generally defined as compensation for services, and the clause aims to stop undue influence and corruption of officials by foreign governments.

“There are a variety of conflict of interest laws that do apply and a few that don’t,” said Norm Eisen, a former special counsel to President Barack Obama for ethics and government reform.

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The president cannot, for example, make money from a foreign government or a bank controlled by a foreign government, Painter said. Trump’s vast real estate holdings include golf courses in the United Kingdom, residential properties in Asia and hotels in South America.

Trump plans to put his business holdings under the control of his three oldest children, but questions have already been raised about that arrangement because they also have official roles in his transition.

But if Trump does not actually give the business to them, he may find himself in extremely dicey territory in a number of matters.

“He would have to scrub every part of these businesses to make sure there are no dealings with foreign governments,” Painter said, adding that Trump should not let foreign diplomats stay in his hotels at foreign government expense.

How also should the National Labor Relations Board, whose members are appointed by the president, sort out matters involving Trump businesses? Painter said Congress should pass new laws making it clear that only career civil service employees should settle such issues, but so far the GOP-controlled Congress seems unlikely to take action.

On Capitol Hill, Democrats have made clear their concerns.

Sen. Benjamin L. Cardin of Maryland, the ranking Democrat on the Foreign Relations Committee, said he would introduce a resolution this week stating the sense of Congress that Trump should convert his assets to simple, conflict-free holdings, adopt blind trusts or take other equivalent measures, in order to ensure compliance with the emoluments prohibition.

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Sen. Thomas R. Carper of Delaware, the ranking Democrat on the Homeland Security and Governmental Affairs Committee, sent a letter to the Office of Government Ethics asking for “assurances” that the agency will “advance a strong ethics program that holds the administration of President-elect Trump accountable for any conflicts of interest.”

And Maryland Rep. Elijah E. Cummings, the ranking Democrat of the House Oversight and Government Reform Committee, sent at least five letters to the panel’s chairman, Jason Chaffetz of Utah, calling for hearings to probe apparent conflicts of interest with Trump and his senior officials. Cummings and Massachusetts Democratic Sen. Elizabeth Warren also asked the Government Accountability Office to examine potential conflicts of interest in the president-elect’s business ties.

So far, Chaffetz has signaled he’s more interested in continuing his investigation into the emails and foundation of Trump’s presidential opponent, Hillary Clinton. He said on Fox News in mid-November, “It wasn’t political targeting at the beginning, so because there’s been a political election, why should I just drop it?”

But depending on how the public responds to Trump’s business tangles, Congress could turn. “The president-elect is just a few senators from being called to account,” said Eisen, now a Brookings Institution visiting fellow.

Outside of Congress, the role of government watchdogs and whistleblowers will also be crucial, he added.

Such groups are gearing up for major efforts opposing Trump’s business ties, even as the president-elect has pledged to make government ethics a priority, a pledge those groups say rings hallow.

Watchdog organizations such as Every Voice and Public Citizen said they did not yet know whether liberal donors would step up their funding, but a surge of contributions may be forthcoming.

“We’re entering an unprecedented time,” said David Donnelly of Every Voice, which advocates a campaign finance overhaul. “It’s not simply about who gets appointed to run the EPA and whether they were a former lobbyist but about what actions will harm children who live near a power plant in Ohio. We are working to translate the policy impact of these decisions to people’s lives.”

Trump’s own business dealings will be a major focus.

“When he was running for office, Trump kept railing about the corruption in Washington, the rigged system and draining the swamp — but he doesn’t believe there are any corruption problems that he has to worry about,” said Fred Wertheimer, who runs Democracy 21, a campaign finance watchdog group. “I think we’re going to be very busy.”