As the House impeachment inquiry intensifies, President Donald Trump has begun relying increasingly on Senate Majority Leader Mitch McConnell to unify Republicans and shore up support.

Trump has even begun phoning McConnell up to three times per day, CNN reported Wednesday.

Trump has also begun raging at Republican senators whom he views as disloyal — most notably lashing out at Sen. Mitt Romney of Utah, but also at Republicans who have not vocally defended Trump.

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President Donald Trump phones Senate Majority Leader Mitch McConnell up to three times per day in a frenzy over the congressional impeachment inquiry, CNN reported, citing a person familiar with the conversations.

His behavior has started to mimic his fury during the Russia investigation, according to CNN, and Trump is relying on McConnell to see him through the turmoil, unify Republicans, and shore up support.

McConnell spokesman Doug Andres denied CNN's reporting, calling it "categorically false."

The House of Representatives has been investigating Trump's conduct during a July 25 phone call with Ukrainian President Volodymyr Zelensky, in which Trump pressed the foreign leader to investigate former Vice President Joe Biden, one of Trump's most prominent political rivals.

Read more: A Fox News poll just found that more than half of American voters want Trump impeached and removed from office

Trump has since urged China to also investigate Biden, drawing even more scrutiny from congressional Democrats and prompting some Republicans to throw up their hands.

Trump has also begun raging at Republican senators whom he views as disloyal — most notably lashing out at Sen. Mitt Romney of Utah. Romney has criticized Trump's efforts to solicit foreign intervention to investigate his political rivals as "wrong and appalling."

Last weekend, Trump called Romney a "pompous 'ass'" in response.

Trump is upset that some Republicans haven't more aggressively defended him

President Donald Trump answers questions from reporters during an event on "transparency in Federal guidance and enforcement" in the Roosevelt Room of the White House, Wednesday, Oct. 9, 2019, in Washington. Associated Press/Evan Vucci

But it's not just outspoken Republicans like Romney who have drawn Trump's ire — he has also grown resentful of Republicans who haven't publicly defended him, according to CNN. Trump has reportedly complained that Democrats are far better at taking cues from their party's leadership than Republicans.

Another complicating factor has been the number of Republicans who have vocally criticized Trump's decision to withdraw US troops from Syria.

A number of Trump's staunchest allies — such as Sen. Lindsey Graham of South Carolina — have been reluctant to criticize him over the Ukraine scandal, but have vehemently condemned his actions in Syria.

Read more: Senators announce a bipartisan bill to impose 'severe sanctions' on Turkey and block military sales

In response, the White House has begun attempting to quietly woo back congressional Republicans by hosting private dinners and holding gatherings at Camp David, The Washington Post reported Wednesday.

"The administration looks forward to continued engagement with members about many real issues facing the American people and sadly, even the Democrats' shameful politically motivated ones like this fake impeachment," White House spokesman Hogan Gidley told The Post.