By Dana Milbank - There are those who say that the tea party is fading in influence, but nothing could be further from the truth. In fact, the movement is on the cusp of achieving what once seemed nearly impossible: keeping the Senate Democratic...

...In the 2010 cycle, tea party candidates caused the Republicans to lose three Senate seats easily within their grasp: Sharron Angle allowed Democratic leader Harry Reid to keep his seat in Nevada, Christine O’Donnell handed Joe Biden’s former seat right back to the Democrats in Delaware, and a tea party favorite in Colorado, Ken Buck, lost a seat that was his to lose.

[Note from Carloz: In a related article today, LeRoy Goldman blames a fourth 2010 Senate seat loss on a Tea Party candidate: John Raese in West Virginia. Goldman notes, "The death of longtime Democratic Sen. Robert Byrd in 2010 resulted in another open seat battle... In the general election, he [Raese] was opposed by the state's governor, Democrat Joe Manchin. In September 2010, Raese told Real Clear Politics, 'The tea party is a little bit to the left of me.' He lost to Manchin 53 percent to 47 percent."]

Now, tea party picks are in jeopardy of losing two more races that heavily favored Republicans: Richard Mourdock, who beat longtime Sen. Richard Lugar in the Indiana Republican primary, is struggling against Democrat Joe Donnelly; and Todd Akin, who bested the Republican establishment’s favorite in the Missouri Senate primary, is expected to lose to the onetime underdog, Democratic Sen. Claire McCaskill, because of Akin’s infamous comments on “legitimate rape.”

Democrats and affiliated independents now have 53 seats to the Republicans’ 47. The way things look now, they seem likely to end up with 51 or 52 after the election; if President Obama is reelected, they would keep control of the chamber with 50 seats because Vice President Biden would have the tiebreaker vote. This would mean that the seats the tea party cost the Republicans — between three and five, depending on the outcomes in Indiana and Missouri — will have kept the Democrats in charge.

For the tea party cause, the consequences should be fairly obvious. If Obama wins reelection, this would deny Republicans unified control of Congress (GOP control of the House is virtually certain) and diminish their leverage in negotiations with the White House. If Romney wins, it would give Democrats the ability to thwart his agenda and to launch probes of the administration.