Washington (CNN) -- The Kansas Senate seat that Republicans have controlled for the past 80 years looks like it could be in trouble, a new poll finds. Independent candidate Greg Orman now has a 10-point lead in his campaign to unseat three-term incumbent Sen. Pat Roberts, according to a NBC News/Marist poll released Sunday. The survey of 636 likely Kansas voters has Orman with 48 percent of the vote to Roberts' 38 percent of the vote, outside of the poll's 3.9 percentage point margin of error. That represents a five- to 10-point gain for the independent candidate, with polling over the last month judging the race anywhere from a dead heat to a five-point advantage for Orman.
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A new poll finds independent Greg Orman has a 10-point lead against Republican Pat Roberts.
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The survey also gave Democratic Sen. Kay Hagan a four-point lead in the tight N.C. race.
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And in Iowa, polling from the same group puts the Iowa Senate race at a dead heat.
Democrats have placed their bets on an @placeholder victory, going so far as to pull their own nominee from the race to give Orman a better shot at unseating Roberts.