But some of the speaker's allies and Republican senators expect her to within hours begin the process of sending two articles of impeachment -- charging that Trump abused power and obstructed Congress -- to the Senate.
The eventual transfer would end a near-four week limbo since Pelosi's House of Representatives scarred Trump's legacy by making him only the third President to be impeached. The President was accused of using his power to coerce Ukraine into dishing dirt on Democrats, including Joe Biden, a possible 2020 election rival, and then withholding evidence to cover it up.
The House speaker may have now reached the point of diminishing returns in her strategy of holding up Trump's Senate trial to try to force the GOP to admit new evidence and witnesses.
Pelosi argues that her tactic offered time for damning new evidence to emerge about what she says is Trump's abuse of the presidency in Ukraine. She has also repeatedly charged that Republicans are cooking up a sham trial with the President.
But the interregnum may also have let the memory of shocking testimony revealing Trump's apparent misconduct to fade from public memory — potentially dampening the political potency of the case against the President.
There have been clear signs in recent days that political patience with Pelosi's strategy has been wearing thin, even with Democrats.
The unusual power play matching Pelosi against another Capitol Hill giant, Senate Majority Leader Mitch McConnell, allowed Pelosi to demonstrate the power of a majority Democrats believe was handed to them in midterm elections to curtail Trump.
It also underscored her stature in Washington. She made clear that no one would tell her what to do. She demonstrated her control over her own troops when Rep. Adam Smith hastily backtracked on Thursday after urging her to get it over with and transmit the articles of impeachment (Smith later said he issued the clarifying statement because of constituent calls, not due to pressure from Pelosi).
"I'm not delaying indefinitely. I'll send them over when I'm ready," Pelosi said on Thursday, after several Democrats in the Senate also called for her to break the logjam.
Plenty of pressure
But McConnell has piled pressure on the speaker.
"If the Speaker continues to refuse to take her own accusations to trial, the Senate will move forward next week with the business of our people," McConnell said in a floor speech. "We will operate on the assumption that House Democrats are too embarrassed to ever move forward."
When the stalemate eases and the Senate can finally make preparations for Trump's impeachment trial that could begin as soon as next week, there will be an accounting of what exactly Pelosi achieved.
On the face of it, it doesn't look like much. But the speaker may have been playing a longer game while insisting she needed to know the shape of the Senate trial before naming her team of impeachment managers who will make the case against Trump.
She failed to force McConnell to call witnesses and evidence that the White House refused to provide to House investigators, before the trial begins. Republicans have been adamant that there can be no expansion of the probe into Trump, sometimes citing dubious constitutional justifications.
This was always likely to be the case. There's nothing the Senate, as an institution, likes less than to be ordered around by the House. Pelosi's delay may have actually caused wavering members of the House to line up behind their leader and agree to wait until the trial begins to consider witness subpoenas.
McConnell has an increasingly brittle relationship with Pelosi, and there was never much chance that he would cave into her demands and attempt to shape the business of his chamber.
Still, the speaker on Thursday made a case that her strategy had significantly worsened Trump's plight by giving time for more evidence — tying the President closer to the decision to withhold aid to Ukraine to emerge.
Pelosi's delay aimed at helping Democrats
During the standoff, emails also emerged from the Pentagon showing concern over delays in the nearly $400 million in military aid is accused of holding back to pressure Ukraine for political favors.
Some observers were surprised that Pelosi did not claim victory and move on under political cover when former national security adviser John Bolton announced earlier this week that he would testify, if subpoenaed, in a Senate trial -- however unlikely that prospect still seems to be.
Instead, Pelosi staked out a new confrontation with McConnell, telling her members in a letter on Tuesday night that she wouldn't hand over the articles of impeachment until the Majority leader released the text of a Senate resolution in impeachment trial rules. She dug in on Wednesday, saying that Democrats will wait to learn the terms of the trial before sending over the articles and naming impeachment managers.
The delay in handing over the articles of impeachment also appeared to ruin Trump's holiday at his Florida resort. The President fulminated against Pelosi, day after day on Twitter. He still hasn't calmed down as he impatiently awaits the expected Senate acquittal that he will paint as validation.
"Remember her 'speed & rush' in getting the Impeachment Hoax voted on & done. Well, she never sent the Articles to the Senate. Just another Democrat fraud. Presidential Harassment!" Trump wrote in a typically fraught tweet on Thursday.
Pelosi's delay also helped her and Senate Minority Leader Chuck Schumer cultivate the political terrain for the aftermath of a trial that is expected to easily acquit the President, owing to the lack of a two-thirds majority in the GOP-led Senate to make him the first President ejected from office by Congress.
That message — that Trump is unfit and Republicans shielded a corrupt commander-in-chief -- will be at the center of the eventual Democratic nominee's campaign in the fall.
"They don't want documents, the documentation. They don't want witnesses," Pelosi said. "They may want a dismissal, which is proof that they cannot -- cannot clear the President of the wrongdoing that he has put forth."
But in recent days, it has become clear that even some Senate Democrats want to get the trial out of the way, and had begun to believe that Pelosi's delaying strategy had its moment.
"I think you always run the risk that the delay runs into some other big thing happening - so that becomes another delay," said California Sen. Dianne Feinstein in a week when exactly that scenario played out — as Trump's showdown with Iran consumed both chambers of Congress.