Originally posted by the Voice of America. Voice of America content is produced by the Voice of America, a United States federal government-sponsored entity, and is in the public domain. Second Day of Questions in Impeachment Trial, Then a Decision on Witnesses VOA News WASHINGTON - The U.S. Senate will spend a final day Thursday questioning President Donald Trump's defense team and the House lawmakers prosecuting his impeachment case, as a decision looms about allowing witnesses. How quickly the proceedings come to a close will be determined by whether the Republican-majority will approve a request from Democrats to hear from key administration officials. The issue dominated Wednesday's first session, during which senators submitted written questions. The spotlight was on John Bolton, the former national security adviser who wrote in a yet-to-be-published book that Trump told him he was withholding $391 million in military aid to Ukraine until President Volodymyr Zelenskiy publicly announced a corruption investigation into Democratic presidential challenger Joe Biden. Democrats insist Bolton and others must be called as witnesses. Most Republicans, who say Trump did nothing wrong in freezing the aid to Ukraine, do not want Bolton or anyone else subpoenaed or any new evidence entered. WATCH: Senators Take Turns Asking Questions at Trump Impeachment Trial .