Des Moines, Iowa (CNN) -- The polls are tight, the ads are flooding the airwaves, the harsh rhetoric is rising, and the surrogates are stumping hard all over the state. There is one "X-factor" that will put one of the Iowa Senate candidates over the top: Good, old-fashioned door-knocking -- except, it's not old-fashion anymore. Political door knocking is now a data-driven operation, making it as critical a piece of high tech campaign strategies as the endless fundraising solicitations delivered daily to supporters' inboxes. Canvassers only go to targeted households identified by algorithms using early voting/absentee voting data, party registration, voting history, and other micro-targeting information that create a stronger profile of a person or household's likelihood to vote for their own candidates.
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Door-knocking is still playing a role in the campaign for Iowa's open Senate seat
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Canvassers are using algorithms to target voters likely to vote for their candidates
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To track voter data, Democratic canvassers use clipboards while Republicans have turned to a phone app
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50,000 more absentee ballots have been cast so far this year than at this point in 2010
In 2012,65,000 more registered Democrats voted absentee than registered @placeholder.
"In years past the early voting especially was a huge @placeholder advantage; we realized we needed to do something to help catch up."