Linda McMahon (center) visits a senior center in Naugatuck, Conn., this month. Jessica Hill/AP hide caption

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Connecticut GOP Senate candidates Rep. Christopher Shays and Linda McMahon shake hands at a June 14 debate in Storrs. State Republicans vote Tuesday on which candidate will move on to the general election. Stephan Savoia/AP hide caption

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Lugar, in the Senate 34 years, faces a strong Tea Party challenge in next year's GOP primary. Alex Brandon/AP hide caption

toggle caption Alex Brandon/AP