The Tea Party movement scored another victory on Tuesday, helping to propel a dissident Republican, Christine O'Donnell, to an upset win over Representative Michael N. Castle in the race for the United States Senate nomination in Delaware.

Mr. Castle, a moderate who served two terms as governor and had been reliably winning elections for the last four decades, became the latest establishment Republican casualty. Republican leaders, who had actively opposed Ms. O'Donnell, said the outcome complicated the party's chances of winning control of the Senate.

Read the entire New York Times article here.