It was a one-two — and then three — punch.

Within minutes of each other Tuesday, President Trump's former campaign chairman Paul Manafort was found guilty on eight counts related to financial fraud, and his former longtime lawyer Michael Cohen pleaded guilty to eight counts, including campaign finance violations he alleged he president directed him to make. Then, Rep. Duncan Hunter, the second congressional Republican to officially endorse Mr. Trump's candidacy, was indicted on corruption charges for allegedly misusing campaign finance funds.

And Democrats seized on the news.

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"The charges against Congressman Hunter are further evidence of the rampant culture of corruption among Republicans in Washington today. Once again, one of President Trump's earliest supporters in Congress has broken the public trust and abused his position to enrich himself and his family," House Minority Leader Nancy Pelosi said in a statement, two weeks after the Justice Department announced the indictment of the first member of Congress to endorse Mr. Trump, Rep. Chris Collins.

"While House Republicans enrich themselves and their special interest donors, Democrats are committed to cleaning up corruption to make Washington work for everyone," Pelosi added.

Only hours before the Manafort and Cohen news dropped Tuesday, Democratic Sen. Elizabeth Warren — herself a potential 2020 presidential contender — introduced comprehensive ethics legislation to help clean up what she called the "cancer" of corruption plaguing the nation's capital.

Democrats — who polls currently show are more likely to take the House in November than not — have already harped on the spending and potential conflict-of-interest issues of the Trump administration. Ex-Trump administration officials including Scott Pruitt and Tom Price, who stepped down over scandals of their own, were already fodder. But the guilty findings of two high-profile people close to the president or his campaign and the criminal indictments of the two first congressional Republicans to support Mr. Trump -- one for insider trading and the other for spending campaign funds for personal use -- crystallized the message.

The anti-corruption message is one Democrats used, successfully, to flip the House in 2006, as Republicans faced scandals involving lobbyist Jack Abramoff and congressmen Tom DeLay and Mark Foley.

But one Democratic source familiar with 2018 midterm strategy says Republican scandals won't overwhelm Democratic messaging in 2018. Nationally, Democrats are focusing much of their messaging on kitchen-table issues, the source said — and although part of that includes defending the democracy and holding Mr. Trump and Republicans accountable, the source said the "culture of corruption" issue won't be huge focus this fall.

A Democratic strategist spoke along similar lines.

"What we advise candidates is that everyone is talking about Trump," the strategist told CBS News. "You can't turn on the TV and not see Trump. You are not going to be the voice that moves people (on) Trump."

Candidates need to focus on how they can help increase wages, focus on health care — frankly, those "bread-and-butter issues that really matter to families," the strategist said.

Can Republicans' ethical crises enter into the equation for Democrats in the months ahead?

"That's kind of dependent upon the race," the strategist said. "So, how do you take that and pivot it back to your message?"

That pivot would need to be something like, "While the administration is focused on enriching itself, I want to make sure that your family is taken care of," and honing in on that message, the strategist said.

Democratic strategist Basil Smikle said it shouldn't be an either-or messaging strategy when it comes to kitchen table issues and scandals.

"Democrats need a two-pronged approach: A standardized message emphasizing the hypocrisy of the president and Republican leaders that sidled up to him who were complicit in their mutual disregard for voters interests," Smikle said. "But we must also offer specific solutions to strengthening institutions that Trump has damaged and economic solutions that he's neglected."

Pelosi, in a "Dear Colleague" letter to fellow Democrats obtained by CBS News' Nancy Cordes, gave weight to that two-pronged approach.

"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," she wrote. "As November rapidly approaches, we must also stay focused on delivering our strong economic message to hard-working families across America that we are fighting For The People."