If Donald Trump’s presidency feels like a roller-coaster ride, with each hair-raising turn of events quickly giving way to a new one — and opinions about him constantly in motion — the results of CQ Roll Call’s Capitol Insiders Survey in 2019 buttress that view.

Few congressional staffers thought, at the beginning of the year, that Trump was headed for impeachment. But the results of CQ Roll Call’s October poll are unambiguous: Staffers in both parties overwhelmingly believe Trump will become the third president in U.S. history to be impeached.

Still, impeachment is proving deeply divisive, with Republicans characterizing it as nothing more than a partisan witch hunt, while Democrats insist the presidency’s integrity is truly at stake. 

Four times this year, CQ Roll Call has polled congressional staffers about their views on impeachment. The evolution of their views shows just how much the story of Trump’s effort to get Ukraine to investigate Joe Biden, his political rival, has resonated where past charges against Trump have not.

[Trump impeachment makes for tricky messaging for Democrats]

CQ Roll Call conducts its poll by email, using a comprehensive list of staff addresses. The poll is unscientific but draws a steady response, typically 150 to 200 aides.

A dramatic shift

As 2019 opened, Special Counsel Robert S. Mueller III had not yet released his findings on Russian interference in the 2016 election, and on whether Trump’s campaign had cooperated with the Russians, but there was a sense, as his investigation dragged on, that his findings might underwhelm.

In January, only 22 percent of Democratic congressional staffers polled by CQ Roll Call predicted the House would impeach Trump. The conventional wisdom was that Mueller would have to come out with something damning and directly implicate the president to change the narrative.

Speaker Nancy Pelosi was busy deflecting the progressive advocates of impeachment in her caucus in order to protect the 31 House Democrats who gave the party the majority and her the speakership, and who represent districts that Trump won in the 2016 election.

Mueller gave his report to Attorney General William Barr in March and Barr released a summary that seemed to exonerate Trump, stressing Mueller’s view that Trump’s campaign had not conspired with the Russians while downplaying evidence in Mueller’s report that Trump had obstructed the special counsel’s probe.

Still, if Mueller was perturbed, he hardly showed it, declining until July to testify, and then disappointing Democrats with a confused, legalistic presentation. His report said he did not believe his office had the power to charge Trump with obstruction.

Among Democratic aides, the report didn’t move the needle. Only a quarter of Democratic respondents to the April Capitol Insiders Survey said it was time to begin impeachment proceedings, with more than half opposed.

That all changed in mid-September when media reports surfaced that Trump in a July phone call asked Ukrainian President Volodymyr Zelenskiy to investigate Biden. Trump had previously frozen nearly $400 million in military aid to Ukraine, prompting charges of a quid pro quo.

In September, half of the Democratic staffers who filled out that month’s survey supported beginning an impeachment inquiry. Within days, Pelosi called for just that and all but 10 House Democrats supported her, including 21 of the 31 representing 2016 Trump districts.

“As a result of the revelations about Ukraine, it’s not only about politics, but about doing what’s right for the country,” says Jim Manley, a former spokesman for then-Senate Democratic Leader Harry Reid of Nevada.

The dam broke by the October survey, the week of Oct. 21. Almost every Democratic respondent said the House now had reason to impeach Trump, and more than 9 in 10 said it would.

GOP sides with Trump

Republicans mostly agreed in the October poll about the House’s direction. Nearly 3 in 4 GOP respondents said impeachment was a certainty.

Republican aides, however, are rallying to Trump’s side. Only 9 percent said Trump had committed an impeachable offense, with nearly 70 percent saying he did not.

And a nearly identical percentage of Republicans said they thought the impeachment inquiry would, in the end, redound to the GOP’s political benefit.

To Republicans, “It can come across as a three-year investigation in search of a crime,” says Gary Abernathy, a former aide to Ohio GOP Sen. Rob Portman.

Notably, Democrats were less sure of which way the political winds were blowing. Only 48 percent of them in the October survey said Democrats would benefit politically.

On one thing, partisans of both sides agree: The Senate won’t remove Trump from office. Not a single Republican aide thought it would, while only 4 percent of the Democrats did.