Republicans on a Senate panel voted Thursday to authorize a sweeping set of potential subpoenas targeting the origin of the federal investigation into President Trump’s 2016 campaign, with a focus on several senior members of former president Barack Obama’s administration.

The vote in the Senate Homeland Security and Governmental Affairs Committee represents the escalation of an election-year GOP campaign to recast the investigations that consumed much of the president’s first two years in office as the product of backroom manipulation, corner-cutting and subterfuge orchestrated by Trump’s political enemies.

The committee voted along party lines to authorize 36 subpoenas after several attempts by Democrats to delay the vote failed.

“There are times when extraordinary situations require action, whether or not we all agree. The conduct we know that occurred during the transition should concern everyone and absolutely warrants further investigation,” Sen. Ron Johnson (R-Wis.), chairman of the panel, said Thursday.

The Senate Judiciary Committee angrily debated its plans for subpoenas as Chairman Lindsey O. Graham (R-S.C.) said it wasn’t only the Russians who interfered in the 2016 election. The panel delayed its vote to next week as Democrats sought to offer amendments.

“It was the Department of Justice. It was the FBI. It was people who hated Trump and people who had political bias, an agenda to destroy him before he was elected, and after he was elected,” he said Wednesday. “And we’re going to get to the bottom of it.”

To Democrats, however, the Senate investigations instead represent an insidious use of congressional resources to perform a nakedly political task — bruising the Obama administration, and by extension presumptive Democratic presidential nominee Joe Biden, just months before voters decide whether to hand Trump a second term.

The subpoena requests from the two committees would authorize potential interview and document demands from more than 60 individuals, including former FBI director James B. Comey, former director of national intelligence James R. Clapper Jr. and former CIA director John Brennan.

“This motion grants the chair unbridled authority to go after Obama-era officials,” Sen. Dianne Feinstein (Calif.), the top Democrat on the Judiciary Committee, said Thursday, calling the move unprecedented and opposing the effort.

Democrats also said the effort was distracting from more pressing business facing the nation — a global pandemic from the coronavirus, an economic crisis and civic unrest.

“This morning, the Senate Judiciary Committee isn’t voting on legislation to confront the life or death crises before us. Instead, it’s nursing Trump’s wounded ego with a partisan subpoena. Shameful,” Sen. Kamala D. Harris (D-Calif.) tweeted Thursday.

The fruits of the investigation, several of the Democrats warned, could be used by Republicans to fuel campaign attacks on Biden based on events, documents or testimony that has already been evaluated and discounted by independent investigators — such as Michael E. Horowitz, the Justice Department inspector general who found wrongdoing regarding applications for some surveillance warrants targeting a former Trump campaign aide but did not conclude there was political bias against Trump at play.

Sen. Gary Peters (D-Mich.), the top Democrat on the Homeland Security and Governmental Affairs Committee, said the investigation “appears to be a political exercise” and called on Republicans to allow the Justice Department to complete its own investigation into the origins of the Trump probe — one ordered by Attorney General William P. Barr.

“There are other issues that our committee needs to be focused on — not a partisan issue that’s coming up just before an election related to a political candidate,” he said, citing the ongoing civil unrest in U.S. cities and the coronavirus pandemic. “It looks as if it’s a fishing expedition, and we don’t have time for fishing expeditions. We need to be focused on the domestic crises that we have right now in our country.”

Johnson has shown few reservations about directing the resources of the panel — one of Congress’s most powerful oversight organs — against politically sensitive targets that also align with Trump’s own political interests.

Both committees are under clear pressure from Trump supporters who do not believe that the previous probes — including Horowitz’s review — got to the bottom of what they call the “coup” launched against Trump by his political enemies, including Comey and Brennan.

“I think they are reacting to public pressure,” said Tom Fitton, president of Judicial Watch, which had led the pro-Trump campaign against the Obama Justice Department. “There are tens of millions of Americans who are exceedingly frustrated that there’s been zero accountability to date, and I think Republicans are all of a sudden recognizing that. That’s the number one question I get asked: Why hasn’t anyone gone to jail? Why hasn’t anything been done? And the Senate hasn’t done much.”

While Graham has focused his committee on actions inside the Justice Department in 2016 and 2017, Johnson has focused his interest in the State Department — and alleged efforts by officials there to foment law enforcement interest in the allegations of British intelligence operative Christopher Steele. That has been aided by troves of documents handed over by the Trump administration — and more could be on its way.

Johnson and Graham last month sought and quickly received a list of Obama administration officials who sought to deanonymize foreign intelligence intercepts involving Gen. Michael Flynn — exchanges that ultimately led to his prosecution on charges of lying to the FBI. The senators are expected to receive similar information in the coming weeks about “unmaskings” ordered for other Trump campaign officials and potentially members of Trump’s family.

The Flynn unmasking revelations have fueled furious attacks on the Obama officials in the conservative media and from Trump himself, though Democrats argue that the scrutiny of the intercepts involving Flynn was both legal and justified for national security reasons.

Separately from his investigation into the origins of the Trump probes, Johnson is also investigating Burisma, the Ukrainian energy firm that employed Biden’s son Hunter as a board member from 2014 to 2019. The committee voted on party lines last month to authorize subpoenas targeting a Washington public affairs firm, Blue Star Strategies, hired by Burisma to open doors in the U.S. government.

Johnson is conducting both investigations in tandem with Sen. Charles E. Grassley (R-Iowa), the powerful chairman of the Senate Finance Committee, and in both instances, Johnson has indicated he intends to issue findings before the November election. Earlier this year he signaled outright intent to deliver a political impact as he move to issue subpoenas in the Burisma case.

Johnson said he is aiming to have a report on Burisma’s activity — probably focused on its dealings through Blue Star inside the Obama State Department — sometime this summer, with a report on the origins of the Trump investigations in the fall — aligning with Graham’s own timeline of delivering a report in October.

The Burisma probe has sparked more serious Democratic objections rooted in Johnson’s potential reliance on materials provided by Andriy Telizhenko, a former Ukrainian diplomat who worked as a consultant for Blue Star Strategies on Burisma-related matters during Hunter Biden’s board tenure. Telizhenko, Democrats and some Republicans have warned, could be spreading Russian disinformation meant to disrupt the 2020 election.

Aside from the Blue Star materials, which are protected by a nondisclosure agreement, Telizhenko said in an interview last month that he had already shared more than 100 emails with Johnson’s committee sent before and after his Blue Star tenure and has been in routine communication with committee staff.

Johnson told reporters earlier this year that he was treating Telizhenko’s materials with appropriate skepticism and defended dealing with him to uncover how Burisma may have influenced U.S. policy using Hunter Biden’s name for access inside the Obama administration.

Still, the political overtones of the probe have meant hiccups for Johnson. Sen. Mitt Romney (R-Utah) withheld support for a Telizhenko subpoena, forcing Johnson to subpoena Blue Star instead. And Romney said Wednesday that he would back the subpoena of Obama officials only after requesting “adjustments” to exclude inspectors general and to avoid duplicating other committees’ requests. He also signaled his dismay that Johnson was not investigating other matters.

“It’s not, in my opinion, the appropriate priority for the committee,” he said Wednesday. “But he sets the agenda, and there was wrongdoing identified by the inspector general, so I will support it.”

Donald K. Sherman, deputy director of Citizens for Responsibility and Ethics in Washington, said Johnson and other chairmen indeed have wide leeway to direct their panels. But it was notable, he said, that the Trump administration was cooperating with the panel in an apparent effort to embarrass the Obama administration and Biden while at the same time stonewalling Democratic oversight requests in the House.

That, he said, suggested that the Senate probes are political exercises rather than legitimate fact-finding efforts.

“There really aren’t a lot of checks on Congress launching political investigations — we’ve seen it time and time again,” said Sherman, a former Democratic oversight counsel to the Homeland Security and Governmental Affairs Committee. “The more pressing question is why isn’t the State Department treating oversight requests from Republicans and Democrats in the same way?”

David Stern in Kyiv, Ukraine, contributed to this report.