(CNN) Speaker Nancy Pelosi's announcement Tuesday that the full House would vote on sending the articles of impeachment against Donald Trump to the Senate this week -- a move that will formally trigger the start of the trial against the President in the upper chamber -- amounts to a stark concession that her plan to delay that action for nearly a month failed.

When the House passed the two articles of impeachment against Trump -- one for abuse of power, the other for obstruction of Congress -- in mid-December, Pelosi pointedly refused to transmit the articles to the Senate. In explaining that move, she said this at the time: "The next thing for us will be when we see the process that is set forth in the Senate, then we'll know the number of managers that we may have to go forward and who we will choose."

Pelosi's goal was simple: To try to force Senate Majority Leader Mitch McConnell's hand. Pelosi wanted to use her possession of the articles of impeachment to yield promises and/or compromises from McConnell -- most notably on the issue of witnesses being allowed to be called in the Senate trial.

Except that McConnell wasn't playing ball.

"There will be no haggling with the House over Senate procedure," McConnell said earlier this month . "We will not cede our authority to try this impeachment. The House Democrats' turn is over. The Senate has made its decision." And McConnell backed up that no-negotiation position with a show of force: Announcing that he had secured the support of a majority of the Senate to begin the impeachment trial without any decision on witnesses.

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