Pre-recorded campaign calls, or "robo-calls," have become the leading form of campaign communication in the 2008 primary season with 39% of voters nationwide saying they have received at least one; robo-calls now top even mass mailings as the most frequent type of campaign communication received by voters. Some 36% of registered voters say they have received mailings about the candidates, while only 16% say they have received a telephone call from a live person.

The Daily Number is a statistic, updated every weekday and typically drawn from Pew Research Center project findings, that highlights an important trend.

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