Despite losing at least eight seats, and probably nine before all the votes are counted by 2015, Senate Majority Leader Harry Reid (D-NV) has not faced much in the way of a public pushback from his fellow Democrats… until today.

Purple state Democrat Sen. Claire McCaskill (D-MO) revealed on Thursday that she will not back Reid in his role as minority leader in the next Congress.

The revelation came as a surprise when she was asked by reporters if she would stand by Reid. “I will not,” McCaskill replied.

“Yesterday, I met with Harry Reid and told him I would not be supporting him for minority leader,” McCaskill said in a subsequent statement. “I heard the voters of Missouri loud and clear. They want change in Washington. Common sense tells me that begins with changes in leadership.”

Roll Call noted that the currents of discontent are surging just below the Senate Democratic conference’s placid surface.

In 2010, McCaskill drew laughs from a group of reporters when she floated backing the third-ranking Senate Democrat, Sen. Chuck Schumer (D-NY) for majority leader. “I promise I’ll think about voting for you as leader,” she told those who attended that year’s Washington Press Club Dinner. The best jokes, as we know, are those with a grain of truth to them.

Via Jazz Shaw, Reid is not the only person at the center of a Democratic leadership shakeup. In order “to pacify a disgruntled Democrat base,” Shaw wrote, Reid has approached progressive darling Sen. Elizabeth Warren (D-MA) to gauge her interest in taking a leadership role in the Senate. Because, as McCaskill said, the message the voters sent Washington last Tuesday was clearly that the Senate Democratic leadership is not liberal enough.

In the end, however, it’s all just a political display:

Victorious Sen. Mitch McConnell (R-KY) was confirmed his leadership position by acclamation on Thursday, which is likely how Reid will retain his leadership role. McCaskill’s maneuver serves primarily as a political statement, and an unmistakable one at that..

UPDATE:

An earlier version of this post’s headline identified Harry Reid as the Senate majority leader. He will be vacating that role in 2015.