The Tea Party Express, a political action committee based in California, will begin its fifth cross-country tour bus expedition in Napa on Aug. 27, the conservative group announced Wednesday.

The journey will include 29 stops for conservative rallies, culminating in Tampa, Fla., on Sept. 22 for the presidential debate co-sponsored by the Tea Party Express and CNN.

The group, which funneled tens of thousands of dollars to tea party favorites in the 2010 midterms to help them oust incumbents or trounce rivals in four states, has become one of the tea party movement’s most prominent, though often criticized, forces.

After Napa, the tour heads to Nevada, home to Republican Sen. Dean Heller, appointed to replace Sen. John Ensign (R) after he resigned earlier this year. The Tea Party Express and other tea party groups have raised concerns about Heller and initially encouraged the state’s governor to appoint someone else.

The tour will then continue north, hitting most of the early presidential primary states. It will also target states with key elections, including Nebraska, New York, Minnesota and Indiana, according to spokesman Levi Russell.

Last year’s summer tour started in Searchlight, Nev., in clear message to Senate Majority Leader Harry Reid (D-Nev.) that he would be one of their key targets. The group spent $932,000 last cycle in support of the unsuccessful Republican nominee, Sharron Angle. The decision to start in the Golden State will send a similar message to Sen. Dianne Feinstein (D-Calif.), who is campaigning for her fourth term.