President Barack Obama offered some prescriptions for his own Democratic Party on Monday, suggesting that maybe this year's campaigners had not focused enough on the grassroots.

Democrats, the president implied, should be able to win over more Americans, if only they would get out more into the rest of the country.

"I believe that we have better ideas, but I also believe that good ideas don't matter if people don't hear them. And one of the issues that Democrats have to be clear on is that given population distribution across the country, we have to compete everywhere, we have to show up everywhere," Obama said. "We have to work at a grassroots level, something that's been a running thread through my career."

Democrats were unable to win majorities in the House or the Senate, and presidential nominee Hillary Clinton suffered a surprising defeat to Republican Donald Trump.

Obama cited his own career successes in explaining what successful grassroots campaigning looks like.

"I won Iowa not because the demographics dictated that I would win Iowa, it was because I spent 87 days going to every small town, and fair, and fish fry, and VFW hall. And there were some counties where I might have lost, but maybe I lost by 20 points instead of 50 points," Obama explained. "There're some counties that maybe I won that people didn't expect — because people had a chance to see you and listen to you and get a sense of who you stood for and who you were fighting for."

So, Obama said, the challenge facing the Democrats "is how do you dig in there and create those kinds of structures so that people have a sense of what it is that you stand for."