There are a lot of reasons that Senator Mary Landrieu got creamed in her runoff election, by Republican Representative Bill Cassidy.

But I think the most compelling reason is encapsulated in the reaction from Democrats, which is one big collective “yawn.”

Heck, even on the most active political blogs on the left, folks were left wondering if there was even a run-off election this weekend, because the blog wasn’t providing updates. When your base doesn’t care, you’re going to lose.

Of course, one can say that given the Senate already was in Republican control, starting next year, there was little reason to even pay attention to this runoff, even for the Democratic base. Maybe so.

But if Senator Landrieu had been seen as a forceful voice for progressive ideals, it is hard to imagine the Democratic base not rallying to save her. For example, if Senator Elizabeth Warren was in a run-off like that, Senate control wouldn’t matter – the Democratic base would be working overtime to keep her in the Senate.

So, could someone like Elizabeth Warren win in Louisiana?

Lots of speeches and op-eds have been focused on questions like that, as they examine the best way for Democrats to regain footing in a region, the Deep South, that now has 100% Republican representation in Washington.

In the next few days, I’ll write about which of them are right, and wrong, from a communications perspective.

For now, just know that if you can’t make people care, you can’t make people vote.