Rep. Brad Sherman, D-Calif., introduced an article of impeachment in the House of Representatives against President Trump, saying the firing of FBI Director James Comey constituted an act of obstruction of justice. He argues the charge falls under the banner of "high crimes and misdemeanors" spelled out in the Constitution.
Sherman's impeachment article states
In all of this, Donald John Trump has acted in a manner contrary to his trust as president and subversive of constitutional government, to the great prejudice of the cause of law and justice and to the manifest injury of the people of the United States. Wherefore, Donald John Trump, by such conduct, warrants impeachment and trial, and removal from office
It seems Democrats have not learned anything from the 2016 election. They are behaving the same way Hillary Clinton did during her campaign, making the entire race about Trump's fitness for office instead of what voters found to be important. Clinton's campaign assumed wins in Wisconsin, Pennsylvania, and Michigan. Instead, she lost 680,000 votes in those three states down from former President Barack Obama's 2012 total, allowing Trump to win those three states by about 77,000 votes and handing him victory over Clinton.
Democrats are running around beating the drum of corruption to anybody who will listen. Democratic voters hear it. They don't like Trump, but everybody knows that.