Clark Durant

For all the talk about the death of the Tea Party, conservative insurgents have actually had a fairly impressive run in 2012 against establishment Republican Senate candidates. In Nebraska, Deb Fischer came out of nowhere to beat two Republicans who held statewide office. In Indiana, conservative Richard Mourdock sent moderate veteran senator Dick Lugar packing. And in Texas, Ted Cruz is surging in the run-off election against Lieutenant Governor David Dewhurst.

With Democrats defending 23 of the 33 Senate seats up for election in November, the opportunities for Republican pickups abound. Although Republicans will play defense in Maine, Massachusetts, and Nevada, they will almost certainly make gains in North Dakota and Nebraska. Republicans have good opportunities to take Democratic seats in Missouri, Virginia, Montana, Florida, Wisconsin, and Ohio—and then there’s the list of Democratic seats that could become competitive.