Speaker Nancy Pelosi's formal impeachment announcement on Thursday was addressed squarely at skittish members within her caucus.

Why it matters: President Trump wants as many Democratic "no" votes on the board when the inevitable vote to impeach comes, so Republicans are trying to scare House Democrats from red and swing districts.

The big picture: This is a chance for Pelosi to shape the conversation.

Until now, mostly House Intel Chair Schiff — followed by House Judiciary Chair Jerry Nadler — has dominated the stage, and soon it will be in the Senate's hands.

Coming tonight: Pelosi has a CNN town hall at 9 p.m. ET.

Between the lines: In her formal statement, Pelosi used simple declarative sentences to convey the idea there is no alternative:

"The facts are uncontested.”

"Our democracy is what is at stake.”

"The president leaves us no choice but to act because he is trying to corrupt, once again, the election for his own benefit.”

She was a bit more colorful in the press conference that followed:

Pelosi's reply to a reporter trying to bait her into saying she hates Trump: “Don’t mess with me.”

The bottom line: In both cases, Pelosi was clear. For Democrats, she's the boss.

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