The White House memo of a conversation between President Donald Trump and Ukrainian leader Volodymyr Zelensky, released Wednesday, is bad news for the president, according to experts and observers.

"Donald Trump is the most corrupt president in the modern history of this country."

—Sen. Bernie Sanders

In a statement, Stand Up America spokesman Ryan Thomas said the memo (pdf) was "a smoking gun."

"It reveals that Donald Trump unquestionably asked the Ukrainian President to investigate former Vice President Joe Biden," said Thomas.

"This is blatantly impeachable conduct," Thomas added, "and Congress must swiftly act to draft articles of impeachment—and vote."

Advocacy group Public Citizen agreed, saying in an email that it was clear the president should be removed from the White House.

"Donald Trump's abuse of power, corruption, and disdain for constitutional values have been evident since he first took office," the group said. "There is no question in our minds that, on the merits, he should be impeached by the House and convicted by the Senate."

Releasing the memo was intended to absolve the president of blame for his request of Zelensky in a July 25 conversation to investigate Hunter Biden, the son of former Vice President Joe Biden, a candidate for the 2020 Democratic presidential nomination. In the condensed notes from the conversation, Trump asks Zelensky for a "favor"—that the Ukrainian president direct his people to dig into the younger Biden's hiring by Ukrainian gas company Burisma Holdings from 2014 to 2019.

"If they thought this would exonerate them, they made a very bad miscalculation," said Citizens for Responsibility and Ethics in Washington executive director Noah Bookbinder.

Biden's fellow Democratic frontrunners joined the chorus of condemnation.

"Donald Trump is the most corrupt president in the modern history of this country," tweeted Sen. Bernie Sanders (I-Vt.).

Sen. Elizabeth Warren (D-Mass.), who recent polls show overtaking Biden, said on Twitter that the memo isn't at all exculpatory and demanded more information.

"If this is the version of events the president's team thinks is most favorable, he is in very deep jeopardy," said Warren. "We need to see the full whistleblower complaint and the administration needs to follow the law. Now."

"We have no choice but to impeach."

—Rep. Alexandria Ocasio-Cortez

In a statement, Service Employees International Union president Mary Kay Henry said that the impeachment inquiry must go forward to show that nobody is above the law.

"Working people of all colors and creeds are fed up with self-interested politicians using their power and influence to rig the rules in their favor," said Henry. "Congress must exercise its constitutional duty to investigate thoroughly and, if necessary, take action to ensure that we have a democracy that works for all of us."

Impeachment has its hurdles, said Brand New Congress communications director Zeynab Day, but the American people need to know the facts.

"As much as we want to be relieved, we must accept—this is only the beginning. Impeachment can take months, even years," Day said in an email. "This process will no doubt cause further divisions that break across party lines, but the American people deserve to know the truth."

At the end of the day, this isn't complicated, said Rep. Alexandria Ocasio-Cortez (D-N.Y.).

"The President sought to use the powers of the United States government to investigate a political opponent," said Ocasio-Cortez. "We have no choice but to impeach."