Evidently MSNBC’s ratings have been plummeting this year, and not just because it’s August; the comparisons are with similar months last year. August 2013 ratings were 28 percent below those for August 2012.

Why? One hypothesis is that Barack Obama is having a no good, very bad year in may ways — the IRS scandal, Benghazi, drone killings and NSA surveillance — and that his followers are less motivated to watch cable news than they were last year, when he was running for re-election and mostly leading, though just by a bit, in the polls. It’s no secret that MSNBC’s audience is heavily tilted toward liberals, and with bad news coming in it’s possible that liberals are finding other things to do than watch hour after hour of conservative-bashing news.

The interesting question, if that plausible hypothesis is correct, is whether liberals will be less likely to turn out and vote this fall and in 2014 than they were in 2012. Perhaps some numbers maven will see if there is some correlation between cable news ratings and liberal or conservative voter turnout.