Democrats are trying to force a fight over President-elect Donald Trump's business interests.

Because Republicans control Congress, Democrats have no investigative power. They can't make Trump answer questions about how his holdings around the world clash with his duties as president.

But Democrats are pulling other levers — launching letter campaigns, planning to recruit sympathetic Republicans, encouraging outside watchdog groups and petitioning federal agencies to police conflicts themselves.

"Trump seems to believe he's above the law," Representative Elijah Cummings of Maryland, the top Democrat on the House Oversight Committee, told CNNMoney. "That's dangerous for democracy, and it's our duty to look at these situations."

Trump owns or has a position in more than 500 companies, according to a CNN analysis. That includes companies that have done business in 25 foreign countries, including Turkey, Qatar and Saudi Arabia.

He has said he will turn over control of the family business to his adult children, who are also members of his political transition team. Ethics experts stress this would not eliminate a conflict.

Trump's incoming chief of staff, Reince Priebus, has told CNN that the White House counsel will make sure there are no conflicts of interest. The president is generally exempt from federal conflict-of-interest laws.

Related: Trump's family plan to cut business conflicts falls short

"I can use the power of the pen and microphone," said Cummings, whose committee investigates government waste, fraud and abuse. He has written and made public six letters seeking information on potential conflicts posed by a Trump presidency.

That includes a letter Monday signed by every Democrat on the House Oversight Committee, demanding that its Republican chairman, Jason Chaffetz of Utah, start reviewing Trump's financial arrangements.

"Mr. Trump has exhibited a shocking level of disdain for legitimate bipartisan concerns about his conflicts of interest," the letter said.

Chaffetz did not immediately answer a request for comment from CNNMoney.

Sensing that Republicans will stonewall congressional oversight efforts, Democrats are making plans to go around the committee.

Representative Gregory Meeks of New York, who sits on the House Financial Services Committee, told CNNMoney that Democrats can demand federal agencies launch their own investigations.

Inspectors general have the power to audit and investigate their agencies, and they answer not just to their agencies but to Congress.

"They still have to give us a reply as to what they are or not doing," Meeks said.

Representative Maxine Waters of California is calling on the inspectors general of eight agencies, including the Treasury and Justice Departments, to "root out any potential conflicts of interest."

As an example, she cites Trump's $360 million debt to Deutsche Bank. The Obama Justice Department wants the bank to pay $14 billion to settle claims related to toxic mortgages. Democrats warn that Trump will be in a position to extend friendlier terms to the bank.

Democrats were emboldened by Trump's comments last week to The New York Times. The president-elect told the paper he could run his business and the country perfectly at the same time, and he noted that "the law's totally is on my side."

Related: Trump: Selling my real estate to avoid conflict would be hard

That statement has raised questions about whether Trump even intends to remove himself from his business operations while he's president.

In a CNN poll last week, 59% of respondents said Trump had not made adequate plans to separate his business interests from his responsibility to the public.

Cummings said his office has been flooded with calls from concerned constituents.

"Trump is largely responsible for creating all sorts of doubts about elected officials using their position for their benefit, and now he has opened the door for him to do the same thing," Cummings said. Trump constantly railed during the campaign about a "rigged system."

Still, Democrats know they will need Republican support and may target Republicans, including Senator Lindsey Graham of South Carolina, who have criticized Trump in the past. Graham has called for an investigation into Russian interference in the election.

At least one Republican in Congress, Justin Amash of Michigan, has called Trump out on conflicts. "You rightly criticized Hillary for Clinton Foundation," he tweeted last week. "If you have contracts w/ foreign govt, it's certainly a big deal too #DRAINTHESWAMP."

You rightly criticized Hillary for Clinton Foundation. If you have contracts w/foreign govts, it's certainly a big deal, too. #DrainTheSwamp https://t.co/boUkAfbF6S — Justin Amash (@justinamash) November 22, 2016

Amash's criticism is also significant because he sits on the House Oversight Committee.

The conservative-leaning editorial boards of The Wall Street Journal and New York Post have called on Trump to liquidate his assets or find an ethical resolution.

Related: Wall Street Journal to Trump: Liquidate your holdings

"Even the appearance of monetizing the presidency as another Trump brand would be outrageous," wrote the Post.

Breitbart, the far-right website formerly run by Trump's senior adviser Steve Bannon, went so far as to write last week that Trump has "yet to find a convincing answer to the conflicts of interests that his vast business empire will pose as he takes the oath of office."