Updated

The Tea Party Express bus will barrel back into Harry Reid’s home turf Oct. 18th as part of its final national tour of 2010, the group revealed Monday night.

The self-described “federal political action committee” and tour de force behind several primary election upsets will kick off its “Liberty at The Ballot Box” tour with a rally in Reno, Nevada, where it is backing Reid challenger Sharron Angle. In the final two weeks before the midterm elections, the bus will rumble through 28 cities in 17 states on its way to a November 1st rally in Concord, New Hampshire.

Based in Sacramento, California, the Tea Party Express launched its first tour in August 2009 as part of an anti-tax “March on D.C.” widely attended by other tea party groups across the country. A second bus tour followed in autumn of that year, and a third was launched in March with a large rally, headlined by Sarah Palin, in Reid’s hometown of Searchlight, Nevada.

The excess of $5 million dollars the group has funneled into races across the country, its targeted advertising campaigns, and scrappy grassroots ethos have caused consternation among Democratic and Republican incumbents alike. Republican Senators Bob Bennett in Utah, Lisa Murkowski in Alaska, and Mike Castle in Delaware have been among the latest incumbents to lose out to a Tea Party Express candidate in the primaries. Spokesman Levi Russell has said the group is planning to return to Alaska at the beginning of October to unveil an ad campaign for Joe Miller, whom Murkowski is challenging in a write-in campaign after being taken down in the primary.

The “Liberty at The Ballot Box” tour is scheduled to stop in Kentucky and Delaware, where Tea Party Express favorites Rand Paul and Christine O’Donnell are respectively vying for their states’ Senate seats.