Washington (CNN) -- The Chamber of Commerce is launching an ad featuring Kentucky Sen. Rand Paul, a favorite of libertarians, to build support for Alaska Republican Senate hopeful Dan Sullivan, who faces a challenge from libertarian third party candidate. Republicans and their allies have begun work to limit how much support third party candidates draw away from GOP candidates in states which could determine control of the Senate. In the ad Paul uses language libertarians would like to tout Sullivan, who is locked in a tight race against first term Democratic incumbent Sen. Mark Begich. Mark Fish, past chairman of the state's libertarian party, is running as well and is the wild card there because drawing even a small amount of votes away from Sullivan could prove the difference in this key race.
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Republicans fear third party candidates in several key Senate races, including Alaska
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The Chamber of Commerce has launched ads featuring Kentucky Sen. Rand Paul
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Paul is a favorite of Libertarian leaning Republicans
"In states like @placeholder, the Chamber is focused on the independent swing vote, and we think Sen. Paul is well positioned to deliver a message that appeals to them.