WASHINGTON — Sen. Ron Johnson, R-Wisc., defended President Donald Trump’s recent calls for China and Ukraine to investigate former Vice President Joe Biden in a combative "Meet the Press" interview Sunday morning during which he accused Democrats and the media of trying to sabotage the Trump administration.

“Let me tell you why I’m pretty sympathetic with what President Trump has gone through,” Johnson said when asked about allegations of an effort by the president and his administration to link military aid for Ukraine to promises from the government there to investigate Biden and the origins of former special counsel Bob Mueller's investigation into foreign interference in the 2016 election.

“I’ve never in my lifetime seen a president, after being elected, not having some measure of well wishes from his opponents. I’ve never seen a president’s administration be sabotaged from the day after the election.”

Johnson has emerged as a one of the key congressional figures in the debate over whether Trump’s request of Ukrainian President Volodymyr Zelenskiy to investigate unproven claims against Biden and his son, Hunter Biden, amounts to an abuse of power. That issue is central to the House Democratic impeachment inquiry.

As chairman of the Senate Homeland Security and Governmental Affairs Committee, Johnson was a vocal supporter of that military aid to the country.

Text messages released Friday show State Department officials discussing a link between the administration’s goal of getting Ukraine to launch investigations and scheduling the Ukrainian president for an official White House visit.

But Johnson said that when a diplomat raised the prospect of a quid pro quo to him over the summer, he reached out to the president who “vehemently, adamantly” denied any link between the ask and the aid.

Instead, Johnson argued that Trump has a right to ask foreign governments to help America investigate the origins of the allegations that ultimately became central to Mueller’s investigation.

“I’m here to report today that, unlike the narrative of the press that President Trump wants to dig up dirt on his 2020 opponent, what he wants is an accounting of what happened in 2016. Who set him up? Did things spring from Ukraine?” Johnson said.

The combative interview prompted frustration from Sen. Chris Murphy, D-Conn., who followed Johnson’s interview.

“Ron’s a good friend, but I’m deeply scared by the positioning that Republicans have chosen to take. That interview was just a giant green light to the president of the United States to continue to solicit foreign interference in U.S. elections,” he said.

“This is wild, the lengths to which Republicans are going to try to avoid being criticized by this president.”

And he pointed to those recently released texts to accuse the Trump administration of mixing diplomacy and official business.

"The texts make it clear that there was a quid pro quo on the table, that the State Department, the White House, the president's personal lawyers were all working to get Ukraine to interfere in the 2020 election in exchange for access to the White House and likely the resumption of aid," he added.