A growing chorus of Senate Republicans on Wednesday expressed frustration with President Trump for how he handled the firing of FBI Director James Comey.

"It could have been handled, I think, better," Sen. Pat Roberts, R-Kan., told the Washington Examiner.

Republican critics, though in some instances sympathetic with Trump's decision, said the president acted too abruptly and without sufficient consultation with Congress and without providing adequate justification — to them or the public.

The error has put undue pressure on Senate Republicans, who control the fate of Trump's forthcoming pick to replace Comey, ceding the moral and political high ground to the Democrats unnecessarily.

Trump fired Comey on Tuesday via a letter hand delivered to FBI headquarters in Washington by a White House aide. Except Comey was in Los Angeles on bureau business and not there to receive it. He found out from television news reports that were airing in the middle of a talk he was giving to FBI personnel.

Roberts, a Marine who has served in Congress for more than 35 years, said Trump should have personally informed Comey of his dismissal.

"I think more of a private meeting with the director would have been [preferable,"] he said.

The Justice Department recommended to Trump that he fire Comey for mishandling the investigation into Hillary Clinton's private email server, saying in documents that as FBI director his actions were unfair to the 2016 Democratic presidential nominee.

The reasoning mirrors Democrats' complaints of Comey during and since the campaign. But even Trump's supporters didn't find the justification credible as to why the president wanted Comey gone.

Coming as it did during an ongoing FBI investigation into Russian meddling in the presidential race that could implicate the Trump campaign, Democrats were able to credibly raise the specter of a cover-up, much to the chagrin of Republicans.

"I'm a little confused," Sen. James Lankford, R-Okla., said. "I'm trying to just figure out timing — why this time, why this moment."

The White House is defending Trump, saying that he acted by the book in how he went about relieving Comey of his job.

Republican Senate aides and party strategists said the White House could have avoided the chaos and much of the political fallout with better planning and execution, and absent Trump's counterproductive tweets.

Rather than moving so swiftly, Trump could have received the Justice Department's recommendation to fire Comey and taken under advisement for a week to 10 days. During that time, he could have held high-level meetings and consulted more broadly with Democrats and Republicans in Congress.

Assuming that Trump already concluded that he was going to make a change, the extra time, and show of deliberation, would have given the White House and GOP allies in Congress time to establish credible justification to fire Comey and provided the public with more confidence in the decision.

Using that period to float potential Comey replacements with unimpeachable resumes also would have reduced the political pressure on Senate Republicans — who hold enough votes to confirm the next FBI director — and made it harder for Democrats to paint Comey's dismissal in a suspicious light.

"They just blew it — just blew it," a veteran Republican operative said, on condition of anonymity in order to speak candidly. "We lost the messaging battle in the first 24 hours. We can get it back, but right now hard."

Democrats moved swiftly to capitalize and turn this story into the dominant issue on Capitol Hill.

A special prosecutor should be appointed to investigate Russian interference in 2016, but senior Trump administration officials are too tainted to make the appointment, they said.

Attorney General Jeff Sessions had previously recused himself from the Russia. Now, they're saying that Deputy Attorney General Rod Rosenstein, who recommended that Trump fire Comey, should recuse himself as well.

"I don't think this a Democratic issue and I don't it's a Republican issue," Sen. Dianne Feinstein, D-Calif., said. "You have an attorney general who is in the middle of a big investigation on covert influence by Russia on our election."

In the field, Democrats see a chance to corner Republicans and win seats in the 2018 midterms.

The Progressive Change Campaign Committee, a liberal activist group, announced Wednesday that its battle plan to confront congressional Republicans in their districts about their healthcare bill would now include a component about asking them to answer questions about Comey's firing.

Democratic strategists are being cautious about the impact of this issue, saying that its likely to be a bigger deal in battleground states like Nevada, and swing House districts like Virginia's suburban Washington 10th district, than in solid conservative territory.

But they believe it would be malpractice to soft-pedal the matter, even at risk of distracting from kitchen table issues like jobs and the economy.

"This is kind of thing that turns independents off and motivates Democrats," said Democratic strategist Rodell Mollineau. "Trump's base is going to stay with him, but you don't' grow your base with actions like this. For those on the Right who say that people don't care — they better hope people don't care."