"It is our duty as Members of Congress to seek the truth, and hold the President and his Administration accountable to the American people, and we will," Pelosi wrote.
"As November rapidly approaches, we must also stay focused on delivering our strong economic message to hard-working families across America."
As for impeachment, Illinois' Dick Durbin, the second-ranking Democrat in the Senate, said, "We're too early in the process to be using these words." That should wait, he said, until Democrats "gather the information."
Republicans, by contrast, eagerly warned about the danger of a Democratic impeachment push as they tried to increase fear, and thus turnout, among Trump's most loyal voters.
"They've never been happy with the outcome of the election in 2016, and I expect them to continue their campaign to reverse the election by whatever means possible," Senator John Cornyn told reporters at the Capitol, referring to Democrats.
Trump lawyer Rudy Giuliani has been even more blunt. "This election is going to be about impeachment or no impeachment," he said during a visit to New Hampshire this month.
Even before the public calls for focus on voters' needs, Democratic candidates in the most crucial Midterm races had already committed to steering clear of the latest legal turmoil surrounding Trump - along with the ever-present question of whether a Democratic takeover of the House would lead to the President's impeachment.
Their fears are that an impeachment debate would distract from other goals, while at the same time alienating the very voters they need to win competitive districts.
"I don't want to see a two-year distraction," said Susan Wild, a Democrat who is favoured to win a key Republican-held House seat in Pennsylvania's Lehigh Valley. "I think, honestly, impeachment proceedings would obviously derail getting other things done in Congress."
Although Wild said activists in her district and her social media feeds are often obsessed with Trump's legal problems, she did not issue so much as a tweet to mark yesterday's developments - joining other Democrats in swing districts with her silence.
Over the past three weeks, the first two members of Congress to endorse Trump for president in 2016 have been indicted, a jury convicted Trump's former campaign chairman of eight charges. The President's former lawyer Michael Cohen pleaded guilty in a Manhattan courtroom to eight counts, including a campaign finance crime - at the direction, he said under oath, of a candidate for a federal office, believed to be Trump.
Backing away from a direct focus on scandals involving the President and his former aides marks a shift in strategy following Democrat Hillary Clinton's failed 2016 presidential campaign, which was heavily focused on exposing flaws in Trump's character.
Most Democrats now think that moral revulsion with political leaders is often only a deciding issue for voters who enjoy a level of economic security that allows them to look beyond their immediate needs.
"You're living it every day in Washington, DC, but we're not," said Ann Kirkpatrick, the front-runner for the Democratic nomination for one of the nation's most vulnerable Republican House seats, in Tucson, Arizona. "I'm not hearing from people about these recent incidents."
Kirkpatrick said her supporters have been raising alarms about issues far closer to home than possible Russian collusion or payoffs to an adult-film actress - the future solvency of Medicare and Social Security, the burden of student loans, the possible threats to abortion rights, and the fate of young immigrants who could lose their legal status to remain in the country.
"I have been going door to door. They are concerned," Kirkpatrick said about the kitchen-table issues. "They are worried. They are fearful."
When she talks to voters about corruption, Kirkpatrick speaks not about Trump's circle of implicated former advisers, but about the role money in politics plays in distorting policy to make it harder for working people to make ends meet.
That is the same message that has been picked up by Wild, who is favoured to win a seat vacated by Congressman Charlie Dent, (R). She has sworn off donations from corporate political action committees.
"I always bring the reform message back not to the notion that president might be a rotten guy but the fact that it impacts the issues people really care about," Wild said.
"The Number One issue on the campaign trail for me is healthcare. I make the not very profound leap to say, 'If you are taking money from Aetna or Blue Cross Blue Shield, how can you be unbiased?' "
Some Democratic senators who are not running for re-election have also chimed in to question whether it is appropriate for Trump's Supreme Court nominee, Brett Kavanaugh, to be confirmed, given the scandal surrounding the President.
"I would suggest that an unindicted co-conspirator to a crime should not be in the business of having the ability to appoint someone to a lifetime position on the highest court in our land," Senator Kamala Harris of California said on MSNBC.
Other Democrats have tried to put pressure on Republicans to comment on the President's troubles, forcing them to choose between alienating Trump supporters and excusing criminal behaviour.
"Cohen's decision to put Trump at the scene of the crime creates a huge challenge for Republican candidates, who now have to figure out how many more shoes are going to drop and whether they really want to continue to stay all-in on Trump," said Geoff Garin, a Democratic pollster working on the Midterms.
There is a long history of Midterm elections swinging in part on corruption scandals.
Republicans won control of the House in 1994 after one current and one former Democratic member of Congress were indicted on a charge of misusing money from the congressional post office for personal use.
Democrats retook the House in 2006 in a campaign that focused heavily on the "culture of corruption" among Republicans, which included a major gambling lobbying scandal.
Democrats began preparing for a similar campaign messaging effort shortly after Trump's inauguration in 2017, with weekly staff meetings in Pelosi's office and an initiative by Congressman John Sarbanes of Maryland to draft anti-corruption reforms, including new ethics rules and stricter campaign finance disclosures, that the party could pass into law if they win back control of the House.
But as Democratic strategists studied the issue, they concluded that it was better to use questions of corruption to "caffeinate" other messages about healthcare, education and taxes.
Too much focus on Trump's behaviour, the alleged duplicity of his aides or foreign interference in the 2016 campaign ran the risks of appearing out of touch with voters' central concerns and alienating voters who supported Trump's election, they found.
Rather than talk about specific corruption in Trump's orbit, they prefer to talk more broadly about the problem in government.
"It's a much more systemic problem now, and we have developed a much more systemic response to it," Sarbanes said. "People just want to see that there is that sense of responsibility and accountability to them and their priorities"
The model for this kind of campaign was run by Conor Lamb, (D), in a March special House election in Pennsylvania. He won a Republican-leaning district by refusing to focus on alleged misdeeds by Trump or his associates. Instead, he wove a message about fighting special interests when he spoke about the Republican tax cuts and the rising costs of healthcare.
That didn't prevent Lamb from receiving an enormous outpouring of support from new Democratic activists, who have mobilised because of their opposition to Trump, and who flooded Lamb's district with the help of new groups such as Indivisible and Swing Left.
Democratic candidates, in other words, have decided they can benefit from Trump's legal headaches without ever mentioning them.
"I find I don't need to talk about it, because the voters are already talking about it," Wild said.
