Mitch McConnell: Impeachment will fail with me as Senate majority leader

Senate Majority Leader Mitch McConnell said in a new Facebook ad that impeachment will fail under his leadership, despite acknowledging last week that he would hold a trial if the House approves articles of impeachment against President Trump.

"Nancy Pelosi's in the clutches of a left-wing mob. They finally convinced her to impeach the president. All of you know your Constitution. The way that impeachment stops is a Senate majority with me as majority leader."

The big picture: Pelosi launched the impeachment inquiry against Trump after it was revealed that he had asked Ukraine to investigate former Vice President Joe Biden and his son, Hunter, over unsubstantiated corruption allegations.

• It's been less than 2 weeks since the investigation began and the House committees conducting the inquiry still have a number of outstanding subpoenas and witness interviews. Yet McConnell already appears to be pronouncing that Trump will be acquitted if impeachment falls to the Senate.

Between the lines: McConnell has long taken pride in killing off Democrats' legislative priorities, telling a town hall earlier this year that he will be the "Grim Reaper" for progressive policies if Republicans retain the Senate in 2020.

• McConnell told CNBC last week that he would have "no choice" but to hold proceedings if the House votes to impeach Trump, but added that "how long you are on it is a whole different matter."

Go deeper: Trump letter dares Pelosi to hold vote on impeachment inquiry