Barry Goldwater was running on the heels of an assassination that left the country reeling and caused a huge sympathy vote.
She had a popular incumbent President campaigning for her furiously; the popular First Lady did likewise.
As someone else already pointed out, the polls are not very accurate. On what basis do we assume either Obama or Michelle are popular?
I recall that soon after Obama was elected, Michelle would go out in public wearing genuinely horrible clothing, while the entertainment media dutifully gushed about her poise and elegant sense of fashion. But her wide boob belts (which she eventually stopped wearing) looked absolutely ridiculous, and her clothing choices are all over the board, as likely to be attractive as they are to be ghastly. Despite their best efforts, the entertainment media never managed to launch a Michelle Obama fashion trend.
The economy is far healthier than it was eight or even four years ago.
That is so easy to debunk. A quarter of young adults below age 35 still live with their parents. If the economy is so good, why aren't they out working and raising families?
The link in my tagline not only gives a good snapshot of the current economy, it allows one to look at the past: 1980, 1990, 2000, 2004, 2008, and 2012. It is an interesting site to poke around. It shows that there are some real issues, which, if not fixed, are poised to cause some major economic problems.
They did succeed in getting elite women (media, Hollywood, etc) to wear sleeveless dresses in the middle of frigid winters. Michelle's workout toned arms caused clothing stores to sell mostly sleeveless dresses for eight years, limiting choices greatly.