By Susan Cornwell

WASHINGTON (Reuters) – The Democratic-led House of Representatives voted on Wednesday to send two formal charges against President Donald Trump to the Senate, clearing the way for only the third impeachment trial of a U.S. president to begin in earnest next week.

Lawmakers voted 228 to 193 to give the Senate, controlled by Trump’s fellow Republicans, the task of putting him on trial on charges of abuse of power for asking Ukraine to investigate political rival Joe Biden and of obstruction of Congress for blocking testimony and documents sought by Democratic lawmakers.

The vote was largely along party lines.

The Senate is expected to acquit Trump, keeping him in office, as none of its 53 Republicans has voiced support for removing him, a step that under the U.S. Constitution would require a two-thirds majority in the 100-seat chamber.

But Trump’s impeachment by the House last month will remain as a stain on his record and the televised trial in the Senate could be uncomfortable for him as he seeks re-election on Nov. 3, with Biden a leading contender for the Democratic nomination to challenge him.

“We are here today to cross a very important threshold in American history,” House Speaker Nancy Pelosi said on the House floor before the vote.

Pelosi, who launched the impeachment inquiry in September after earlier resisting such a move centered on Trump’s actions related to Russian interference in the 2016 election, named a seven-member team of House Democrats to serve as prosecutors at the Senate trial. The House voted to approve them.

House Intelligence Committee Chairman Adam Schiff, a former federal prosecutor, was selected to head the team of House “managers.” The White House has yet to unveil its defense team. The trial will overseen by U.S. Chief Justice John Roberts.

Senate Majority Leader Mitch McConnell, a Republican, has said opening statements in the trial were expected next Tuesday.

A pivotal event in Trump’s impeachment was a July 25 telephone call in which he asked Ukraine’s president to open a corruption investigation into Biden and his son, as well as a discredited theory that Ukraine, not Russia, interfered in the 2016 U.S. election.

Democrats have called this an abuse of power because Trump asked a foreign government to interfere in a U.S. election for his own benefit at the expense of American national security. Biden is one of 12 candidates vying for the Democratic nomination to face Trump in the presidential election.

Republicans have argued that Trump’s actions did not rise to the level of impeachable offenses. They have accused Democrats of using the Ukraine affair as a way to nullify Trump’s 2016 election victory.

No U.S. president has been removed as a direct result of impeachment. Richard Nixon resigned in 1974 in the Watergate corruption scandal before the full House could vote on articles of impeachment, while Andrew Johnson and Bill Clinton were impeached by the House, respectively in 1868 and 1998, but not convicted by the Senate.

Clinton’s trial lasted five weeks. If the Senate conducts the Trump trial along those lines, as McConnell has suggested, the televised Senate proceedings against the president would still be going on while the first nominating contests of the 2020 presidential election were underway in Iowa and New Hampshire.

Schiff, 59, spearheaded the House impeachment investigation and he is a frequent target of Trump attacks. Trump in December called Schiff, who served as a federal prosecutor in the U.S. Attorney’s Office in Los Angeles for six years, “a deranged human being.”

Schiff urged Republicans to allow more evidence and witnesses at the trial.

“Americans overwhelmingly want a fair trial in the Senate, fair to the president and fair to the people. Senators must demand to see and hear the full evidence, including the documents and witnesses the president has blocked,” Schiff said in a statement.

Democrats want Trump’s former national security adviser John Bolton to be called as a witness, which could prove damaging to Trump. Other impeachment witnesses have said Bolton was a vocal critic of the effort to pressure Ukraine.

The House managers include four men and three women, with two African American lawmakers and one Hispanic lawmaker. Other managers include Jerrold Nadler, 72, who crafted the two articles of impeachment against Trump as House Judiciary Committee chairman, and Val Demings, a former police chief of Orlando, Florida.

“The emphasis is on litigators, the emphasis is on comfort level in the courtroom, the emphasis is making the strongest possible case to protect and defend our Constitution, to seek the truth for the American people,” Pelosi said in announcing the House managers.

The White House greeted the announcement of the House team with scorn, with White House spokeswoman Stephanie Grisham saying Trump “expects to be fully exonerated.”

“The naming of these managers does not change a single thing,” Grisham said in a statement. “President Trump has done nothing wrong.”

(Additional reporting by David Morgan, Doina Chiacu and Richard Cowan; Writing by Alistair Bell; Editing by Andy Sullivan and Will Dunham)