WASHINGTON (Reuters) - If Democrats win control of the U.S. House of Representatives or Senate next month, nearly every aspect of Donald Trump’s presidency could face swift examination – from his long-elusive tax returns to possible business ties with Russia and conflicts of interest, congressional sources say.

While numerous probes have been expected if Democrats win a majority in the Nov. 6 elections, the sequencing and scope of their inquiries has only begun to emerge in recent talks among party leaders and prospective committee chairs.

Leaders are clear about what’s not on the agenda: impeachment of Trump – at least until the outcome of Special Counsel Robert Mueller’s probe of Russian meddling in the 2016 U.S. elections and possible Trump campaign collusion with Moscow.

But congressional aides say Democrats would move quickly to obtain Trump’s tax returns to look for business ties to Russia and possible conflicts with the Republican president, his family businesses and U.S. government interests, along with a possible examination of his handling of security clearances.

(Congressional election battlegrounds interactive graphic: tmsnrt.rs/2OqGizy)

Trump has refused to release his tax returns, unlike recent U.S. presidents.

Polls show Republicans likely to lose control of the House while possibly expanding their majority in the Senate. Few congressional aides and leaders will speak openly about the Democrats’ investigative agenda.

Democratic majorities in the House or Senate would bring more money and staff for investigations that could derail or delay Trump’s agenda, but aides said Democrats will still aim for some bipartisan cooperation lest their push seem too overtly political ahead of the 2020 presidential election.

Senate Majority Leader Mitch McConnell, in an interview with Reuters, said there is a risk the Democratic probes could be “reminiscent of the late 1990s when we thought it was a good idea politically to impeach Bill Clinton and the public got mad at us, and felt sorry for him.”

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“It could end up not working well for them, at all,” McConnell added.

‘TWO-LANE’ APPROACH

Democrats are poised to act on what they see as a “crisis of corruption in the Trump administration,” Democratic Representative Elijah Cummings told Reuters. “The waste, fraud and abuse is plain to see.”

If Democrats take the House, Cummings would likely be the chairman of the Committee on Oversight and Government Reform, which can examine any federal agency, person or company. He is now the panel’s top Democrat.

During Trump’s presidency, Democrats on that committee have sought 64 subpoenas, which Republican committee members have denied. If Democrats win control of the House, those subpoenas would not suddenly be issued all at once, aides said. But they offer a roadmap of Democrats’ intentions.

Cummings said he would take a “two-lane” approach, examining Trump’s businesses and potential conflicts of interests, while also probing “day-to-day” issues such as prescription drug pricing, voter suppression and questions about citizenship added to the 2020 U.S. Census.

Another early item on the agenda would likely be Trump’s revoking of security clearances from perceived political enemies and his granting of an interim security clearance to an aide who later resigned amid allegations of spousal abuse, aides said.

Cummings would also examine the use of private email at the White House by Trump’s son-in-law and aide Jared Kushner, aides said. Democrat Hillary Clinton’s use of private email as secretary of state was an issue in the 2016 presidential election.

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The oversight panel later sent a bipartisan letter to the White House seeking information on Kushner’s emails but got no response. Cummings would issue a subpoena if needed, according to the aides.

Probes into Trump would also be conducted by the House Judiciary Committee, the tax-writing Ways and Means Committee and the Permanent Select Committee on Intelligence. There is no plan for a special temporary committee, but Democratic leaders would coordinate investigative efforts with the heads of the committees, aides said.

The committees would spend January organizing, with investigations cranking up as soon as February, they added.

The Ways and Means Committee would use its authority to request Trump’s tax returns from Treasury Secretary Steven Mnuchin. The judiciary and intelligence committees could then use the returns to dig into whether Trump got anything of value from foreigners or had business ties to Russia.

Senate Democrats have a list of Trump-related concerns that runs about 100 pages, according to a document seen by Reuters.

Adam Schiff, the top Democrat on the House intelligence panel, wrote on Friday in the Washington Post that the Republican-controlled Congress had abdicated its oversight duty and “been complicit in some of the president’s most egregious attacks on our democratic institutions.”

Schiff said Democrats must “restore Congress as an equal branch and check the ambition of an imperial and erratic president.”