Strong Republican presence at top of the ticket to boost GOP advantage in State Senate

Current partisan split
Republican: 21
Democrat: 14

Incumbents
Republican incumbents: 15
Open Republican seats: 6
Democratic incumbents: 6
Open Democratic seats: 8

Unchallenged seats
No Republican on the ballot: 3
No Democrat on the ballot: 10

Analysis
The Democratic Party is yielding nearly 30 percent of the seats in the upper chamber this year, failing to run a candidate in 10 of 35 districts. Democrats narrowly picked up a few GOP seats in 2008 that should return back to the Republicans this cycle (e.g. SD 07, SD 16). Add to that the strong Republican candidates at the top of the ticket for governor and U.S. Senate, and the GOP should be able to pick off a few more seats and take control of all but the bluest of Senate districts in 2010.

Projection
Partisan shift: GOP +4
Partisan control: GOP hold

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