Explosive testimonies Wednesday and Thursday by credible witnesses have sealed president Donald Trump's impeachment by the Democrat-controlled House.

Action now shifts to the Republican-controlled Senate where Trump's exoneration might not all be that certain in a trial that might yet conceivably lead to Trump's conviction and ouster as president. It all depends on what happens between then and now.

Trump is expected to be impeached by the House on Christmas week. The last nail in his coffin was driven in by his own appointee, Gordon Sondland, the U.S. Ambassador to the European Union, who testified under oath Wednesday he and other officials acted under Trump's express orders to illegally withhold military aid for Ukraine in exchange for Ukraine investigating Joe Biden. There definitely was a quid pro quo, asserted Sondland.

Unnerved Senate Republicans are now circling the wagons to ensure the bid by Democrats to find Trump guilty of impeachable offenses in the Senate fails. A Republican senator cited by media said the GOP is considering a full trial since this will give Trump the ability to clear his name while ensuring the perception he has something to hide. Republicans have to decide if the tactic of allowing Democrats to lay out their evidence and make their case in a period of only two weeks is the best course of action to protect Trump.

Senate sources quoted by CNN said the two-week timeline isn't set in stone and might even backfire on Republicans if the deadline is perceived as arbitrary and biased. It's also clear that no one is certain how long the impechment process in the Senate might take.

Some analysts believe Republicans will move to dismiss the impeachment only after Democrats present their case. This strategy is fraught with political and legal risks, however. GOP senators are working with the White House to prepare for the Senate impeachment trial.

US Ambassador to the European Union, Gordon Sondland, was a major donor to Donald Trump's 2016 election campaign
US Ambassador to the European Union, Gordon Sondland, was a major donor to Donald Trump's 2016 election campaign AFP / Daniel MIHAILESCU

On Thursday, a group of Republican senators discussed among themselves about how a Senate trial should be conducted after the House impeaches Trump. At this discussion were White House counsel Pat Cipollone, and GOP senators Mike Lee of Utah, John Kennedy of Louisiana, Ted Cruz of Texas, Lindsey Graham of South Carolina and Tom Cotton of Arkansas.

"We talked about where things stand and where things are headed," said Sen. Graham, noted CNN.

There were also discussions about how to deal with the anonymous whistleblower whose complaint launched the impeachment inquiry. There is no decision on whether to unmask this person and compel him or her to testify.