The CBS Evening News’ “Presidential Candidates” series begins tonight, in which Katie Couric asks the same questions to Sens. John McCain and Barack Obama, and the answers air back-to-back.

Tonight’s questions could get some interesting responses:
• “Why do you think there has not been another terrorist attack on U.S. soil since 9/11? And as President, how would you prevent that from happening again?”
• “What one personal flaw do you think might hinder your ability to be President of the United States?”

The series runs every Wednesday.

Also, On ABC’s World News, a series called “What’s the Difference,” airs all week. The series takes a look at the difference between the presidential candidates on key issues. David Wright‘s report last night focused on the economy.

Click continued to see the CBS Evening News “Primary Question” that got the most attention, regarding candidate infidelity…

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