Watch: Senate debates critical witness vote in Trump's impeachment trial

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President Donald Trump's impeachment trial is scheduled to resume Friday afternoon, with senators aiming to vote on whether to include additional witnesses and documents.

Senate Majority Leader Mitch McConnell, R-Ky., has been working all week to lock down enough votes within his 53-member caucus to block a Democratic attempt to admit additional evidence in the trial.

If Friday's vote on new witnesses fails, the Senate could move forward with a final vote on whether to convict or acquit the president as early as Friday afternoon. The State of the Union address is scheduled for Tuesday.

The vote comes a day after House impeachment managers and Trump's legal team fielded two days of queries from senators.

House impeachment managers, a team led by Rep. Adam Schiff, were asked to expound on why additional witnesses and documents would be central in Trump's impeachment trial.

On the other side, the defense, led by Trump's personal lawyer Jay Sekulow, was primarily asked about the standards of impeachment and the possible consequences associated with it. They were also pressed on the question of corrupt motives.

The House voted to impeach Trump in December on articles of abuse of power and obstruction of Congress. Democrats accuse Trump of withholding congressionally appropriated military aid to Ukraine while pressuring the country to announce probes into former Vice President Joe Biden and his son, as well as a debunked conspiracy theory about 2016 election interference.

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