The Census Bureau’s $2.5 million purchase of a 30-second ad during the third quarter of Sunday’s televised Super Bowl is making news today, following criticism from U.S. Sen. John McCain (R-AZ), who called the buy “out of touch with what’s going on in the real world” where Americans are hurting because of the poor economy.

The Census Bureau defended the ad, saying its own research indicates that few Americans are aware the 2010 Census is coming in March, and the Super Bowl ads are a much-talked-about means of building that awareness.

By midday, McCain’s criticism, and the Census Bureau’s defense, had generated items in The Washington Post, The Hill blog, as well as Fox News (where McCain raised his objections to the ad yesterday).

A recent Pew Research Center survey about census awareness found that most Americans know something about the census and think positively of it, but that knowledge and positive attitudes are lower among some key sub-groups.

As to whether census advertising is effective, an evaluation of the 2000 Census by the National Research Council, cited in yesterday’s posting, said that linking ads to individual behavior is “typically very difficult in market research,” but it was “likely” that advertising and other outreach boosted participation, in part by creating a wave of good feeling about the national headcount.