Barack Obama’s economic speech Wednesday at Knox College in Galesburg, Ill., was titled “A Better Bargain for the Middle Class.” In the course of the speech, Obama used the phrase “middle class” 20 times. The message was inescapable: the president and Democrats care about the middle class.

The Galesburg speech was just the latest in a very long list of examples of Obama and his allies stressing that their policies will be good for the middle class. Maybe they’re wrong. Maybe it’s just lip service. But the president and his fellow Democrats make a point to say the phrase “middle class” over and over and over and over and over. They send a message through sheer repetition.

Republicans — not so much. There were entire debates in the 2012 GOP presidential primary race in which the words “middle class” were never uttered. And at the two party conventions, a word cloud created by the New York Times showed that Democrats said “middle class” from the podium 47 times, while Republicans said it just seven times. “Middle class” wasn’t entirely missing from the GOP message — it just didn’t play a very prominent part.

How did that work out at the polls? There are no universally agreed-upon income brackets for middle class, and the income brackets used in the 2012 general election exit polls do not satisfactorily describe the middle class. But there’s no doubt that, according to the exit polls, Obama trounced Mitt Romney, 57 percent to 42 percent, among voters whose household income was between $30,000 and $50,000. That group comprised 21 percent of the electorate. (Obama really trounced Romney, 63 percent to 35 percent, in the 20 percent of the electorate with incomes below $30,000.) Romney won, 52 percent to 46 percent, in the 31 percent of the electorate with household incomes between $50,000 and $100,000, but Obama likely did better in the lower end of that bracket, which, combined with his dominance in the lower and lower-middle income brackets, carried him to victory.

Whatever the specific income level, though, there’s no doubt that a majority of Americans think of themselves as middle class. They’re concerned about economic policies that affect the middle class. And they hear about their concerns more from Obama and the Democrats than they do from Republicans.