April 26: That's the day TV advertising costs drop in Nevada, the Las Vegas Review-Journal reports, meaning campaign ads will be on the rise. It comes about one month before early primary voting begins (May 22) and more than a month before the primary (June 8).

Senate Majority Leader Harry Reid's three potential GOP challengers will likely all hit the airwaves by next week, with the hopes of eventually taking down the most powerful and perhaps most vulnerable member of the Senate.

[Former Nevada GOP chair Sue Lowden] already has spent more than $500,000 in TV and radio ads, which gave her an early boost to the top. She'll likely hit the air again. You'll see a lot more TV ad action from the other leading GOP contenders from now on, too, including from Las Vegas businessman and former University of Nevada, Las Vegas basketball star Danny Tarkanian, who's hoping for an end game burst after slipping behind Lowden.

Former Reno Assemblywoman Sharron Angle, who just won the Tea Party Express endorsement, will get much-needed help from the national group, which plans to start airing ads on her behalf April 26-27.

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