House Speaker Nancy Pelosi signed the articles of impeachment Wednesday afternoon.

The U.S. House officially approved sending President Donald Trump’s articles of impeachment over to the Senate, setting the stage for the historic trial of America’s sitting chief executive in a presidential election year.

The House approved transmitting the articles by a party-line vote of 228 to 193 shortly before 1:30 p.m. The approval of Pelosi’s seven impeachment managers also appropriated taxpayer funds that will be used in Trump’s trial.

The impeachment managers hand-delivered the impeachment articles to the Senate on Wednesday afternoon.

On Wednesday morning and after weeks of delay, Pelosi named the impeachment managers, Democrats who will attempt to convince the Senate that Trump is guilty of impeachable crimes and should be removed from office:

  • House Intelligence Committee Chairman Adam Schiff of California, and lead prosecutor;
  • New York's Jerrold Nadler, chair of the House Judiciary Committee;
  • U.S. Rep. Zoe Lofgren of California;
  • U.S. Rep. Hakeem Jeffries of New York, chair of the House Democratic caucus;
  • U.S. Rep. Val Demings of Florida;
  • U.S. Rep. Jason Crow of Colorado, and;
  • U.S. Rep. Sylvia Garcia of Texas.

House Speaker Nancy Pelosi has named seven impeachment managers for President Donald Trump's upcoming Senate trial: U.S. Rep. Adam Schiff of California, chair of the House Intelligence Committee, and lead manager U.S. Rep. Jerrold Nadler of New York, chair of the House Judiciary Committee U.S. Rep. Zoe Lofgren of California U.S. Rep. Hakeem Jeffries of New York U.S. Rep. Val Demings of Florida U.S. Rep. Jason Crow of Colorado U.S. Rep. Sylvia Garcia of Texas Senate Majority Leader Mitch McConnell expects

Arguments in Trump's trial begin next Tuesday, according to Senate Majority Leader Mitch McConnell.

Impeachment was established in the U.S. Constitution as a way to accuse a president of a crime and then hold a trial to determine if guilty. The first step requires a U.S. House member to introduce an impeachment resolution. The House speaker directs the judiciary committee to hold a hearing to decide whether to put the full measure to a vote by the full chamber. A majority of the committee must approve the resolution. If approved, it moves to a full vote on the House floor. If a majority of the House vot

The House voted Dec. 18 to impeach Trump on charges of abuse of power and obstruction of Congress stemming from his conduct toward Ukraine.

The president himself posted this reaction on social media after the impeachment managers were named:

Trump is the third president to be impeached in U.S. history. The others are Clinton and, in 1868, Andrew Johnson. President Richard Nixon resigned before the House could impeach him.

»Meet the House impeachment managers

Pelosi has been unsuccessfully pressuring Senate leaders to meet her impeachment trial demands, which include hearing from witnesses who were not called during the Democrat-led House impeachment hearings.

»MORE: Who are the major players in an impeachment trial? 

Specifically, Democrats are hoping to call more witnesses during a Trump impeachment trial than they did during House proceedings, citing new evidence of Trump’s alleged misconduct.

»RELATED: Which U.S. presidents have faced impeachment?

Donald Trump has become the third American president to be impeached. Trump has been charged with abuse of power and obstruction of Congress. Led by Democrats, the U.S. House of Representatives passed the articles of impeachment on Dec. 18, 2019. Trump will face trial in the GOP-controlled Senate in 2020, a presidential election year. Presidents Andrew Johnson and Bill Clinton were also impeached. Neither was removed from office.

In the weeks since Trump was impeached, Democrats have focused on new evidence about Trump’s alleged effort to pressure Ukraine to investigate his political rivals and they pushed the Senate to consider new testimony, including from former White House national security adviser John Bolton.

McConnell has advocated for weeks that a Trump impeachment trial would follow the same model as Bill Clinton's in 1999.

President Bill Clinton was impeached on perjury and obstruction of Congress charges on Dec. 19, 1998. He was acquitted by the Senate on Feb. 12, 1999. Fourteen senators from that trial still remain in office. Here's how they voted. Susan Collins, R-Maine. Not guilty on both counts Michael D. Crapo, R-Idaho. Guilty on both counts Richard Durbin, D-Illinois. Not guilty on both counts Mike Enzi, R-Wyoming. Guilty on both counts Dianne Feinstein, D-California. Not guilty on both counts Charles Grassley, R-Iow

But McConnell already has enough votes to defeat any Democratic notions of calling witnesses who did not testify during Trump's House impeachment hearings. Two key GOP moderates, Susan Collins of Maine and Lisa Murkowski of Alaska, both agree with McConnell that a Trump impeachment trial should follow the Clinton guidelines.

The Constitution requires a two-thirds Senate majority to convict in an impeachment trial, thus making Trump’s actual removal from office highly unlikely.