It’s more than attending political meetings. Obama has taken social media and marketing to new heights. While we attend meetings.
That is a very important point. Much has been written about the massive database and targeting operation done by the Obama campaign. In large part what they did is identify specific messages that would win over a voter and then direct those messages to that voter. Many of the messages I saw would never have stood up to widespread public dissemination, but were effective when sent to gullible voters likely to believe them.
For example, people identified as supporters of abortion rights got messages saying things like "Republican candidate so and so fought against a requirement that hospital X provide abortion services...instead a woman would be left to die in the emergency room.."
Of course the truth was that the candidate had opposed a requirement that a hospital without an emergency room, which didn't offer any emergency services, should have to offer training on emergency abortions to its staff, none of whom were remotely qualified for that kind of medical care anyway. The campaign message could never have been made publicly, or broadcast, because it would have been immediately shown to be false. But when sent in an email or letter to a small group of voters the message was not corrected - how would the Republican candidate even know who got the letter?
These highly targeted letters often cited as sources obscure blogs as if they were reliable publications. In one case even the posters on the blog rejected the article, but Obama's allies ran with it anyway.
These highly targeted, and often misleading messages are very effective in generating high turn out of particular groups of people. They do however undermine democracy, but conservatives need to know about the technique, and either neutralize it or use similar, but more ethical techniques.