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CBS/APSeveral Sparsely-Populated Counties Have No Primaries Tuesday Because There Is No One To Run Them
(CBS/AP) Early voting in Texas ended late Friday, with the primary just days away.
Voting results as of Thursday have shown a large turnout among early voters - and demonstrably so among registered Democrats.
According to the Texas Secretary of State's election Web site, 717,469 Democrats have already cast ballots either in person or by mail. That's more than 9% of the state's 7,815,906 registered voters.

Elvira Arredondo casts her vote on the first day of early voting Tuesday, Feb. 19, 2008 in El Paso, Texas. Early voting in the Lone State State's primaries has produced high turnout, but some counties won't be holding a primary at all. (AP/V. Calzada, El Paso Times)
Snip: But as Tuesday's primary and caucus nears, with a decision on the Democratic nominee hanging in the balance, 21 Texas counties won't even be holding primaries.
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http://www.cbsnews.com/stories/2008/03/01/politics/main3895907.shtml