A canary gasping for air.

MSNBC, the avowedly liberal cable news network, is in the ratings tank. In the most recent Nielsen ratings, the marquee primetime shows on MSNBC are down by as much as 40 percent as compared to the same period last year. (Not that the ratings were anything to write home about then, either.)

MSNBC began life as a line extension of NBC News and it was originally intended that it would offer more in-depth and long-form coverage of major news stories. But as the Fox News Channel continued to gain strength at the expense of competitors CNN and MSNBC, MSNBC began pursuing a strategy of leaning left on the premise that success might be found in being for the liberal viewer what Fox News was perceived to be for the conservative viewer.

For a while it appeared to be working. During the 2008 presidential campaign, MSNBC beat CNN for the number two spot against Fox.

But National Review columnist Jonah Goldberg now posits that MSNBC is the proverbial canary in the coal mine. The network was at the peak of its health in 2008 and Obama won. Thus its decline might portend trouble for the next Democratic nominee.

There’s a logical case to be made.

Six years in to the most liberal presidency in U.S. history, not a single important promise of the 2008 Obama “Hope & Change” campaign has come true. Do a Google search on “Obama broken promises” and you get more than a million hits. The worst among those broken promises includes pledging to cut the deficit in half by the end of his first term, promising to not put lobbyists in key administration positions, a commitment to create an, “unprecedented level of openness in government,” and, of course, “If you like your health care plan you can keep your health care plan.”

Obama promised a more enlightened foreign policy that would reduce tensions around the world. Six years later, there is chaos in every corner of the globe, a rapidly growing terrorist threat and a Middle East that now looks as if it might erupt into World War III.

Since Obama took office, median household income in the United States has fallen and then stagnated, economic growth has not exceeded an anemic 2.5 percent in any full year and workforce participation has fallen to levels not seen since the Great Depression.

All of this disproportionately impacts those at the bottom of the economic ladder – the very people liberals claim most loudly to be helping.

Taken all around, liberals – particularly those liberals who are closer to the political center – have little in the way of an Obama record that they can proudly defend. It is most likely these viewers who have given up on MSNBC. The Kool-Aid just doesn’t taste as good as it once did.

If Jonah Goldberg’s canary-in-the-coal mine metaphor is apt, the Democrats may find themselves desperately searching for some fresh air in 2016. That “fresh air” and “Hillary” are seldom used in the same sentence may prove troublesome.