Whoever the Democratic nominee is, they will be attacked over something. I watched the Republican hate machine throw things against the wall with Obama until they finally settled on the fact his father was not American and he was non-white. They tried many other memes first. They throw things against the wall until something sticks.
The Republicans have a base willing to believe that candidate X is a goldfish from Alpha Centauri, but that does nothing to move the needle. They need memes that at least sow some doubt among independents willing to vote Republican or among soft voters who might stay home if convinced both candidates are equally loathsome.
Of all the Democratic candidates Joe Biden has thus far proven to be the most meme resistant.
In politics memes only work when they connect with something people already half believe. The attempts to brand Obama as an acolyte of a crazy preacher failed to catch hold because people couldn't believe that Obama really followed anyone slavishly. The secret Muslim, born in Kenya, part of some weird (as yet) unexplained cult to make a Kenyan citizen president caught hold because a segment of the white public were willing to have their embedded racism and anti-Muslim attitudes stoked by the GOP meme machine. Outside of the target audience the memes completely fell flat, but they had their intended effect within the target audience.
There are some candidates that it would be very easy to accuse of being a socialist and make it stick. There are many video clips of Bernie saying he's a socialist. Trying to pin the socialist label on Biden who worked with the financial industry his entire career and has been criticized for being too cozy with that industry would not work. It also wouldn't work on Steyer or Bloomburg, both of whom became self made billionaires from being capitalists.
I've posted before my analysis of every presidential election since 1960. Extreme right or left candidates tend to lose in blowouts as happened in 1964, 1968, and 1972. Moderate Democrats served a total of 16 years during that time. What was the biggest factor determining win or lose was boring candidates tended to lose most of the time. Mondale, Dukakis, Gearoge HW Bush, Bob Dole, Al Gore, John Kerry, Mitt Romney, Hillary Clinton, and to some extent John McCain all had one thing in common, they were all more boring candidates than their opponents.
Either the party affiliation or policy positions are important to about 80% of the voting public split about 50/50 between the two parties. A generic Democrat or Republican has a built in floor of about 40% of the vote from the minute they win the nomination. The entire battle is for the last 20% or so who are persuadable. This 20% tend to be mostly low information voters who are voting out of obligation rather than really caring much. They make an effort to avoid political news in between presidential elections. This time around that group is probably down to about 5-10% because Trump invades your life even when you try to block him out. But that group is still there.
Among low information voters, likability of the candidates is a big factor. It shouldn't be, but it is. Kennedy vs Nixon, Kennedy was more likable. Johnson vs Goldwater, Goldwater was so unliked Johnson looked fantastic by comparison. The same goes down the list during the TV era. In 2016 we had an unusual situation that both candidates were very unliked and it was a race to the bottom. Trump won in part because he was more entertaining, even if he was also loathsome.
Especially in a re-election year, policy with the challenger doesn't matter that much. The #1 issue is whether the incumbent should be re-elected and for over 50% of Americans that answer is already "no". Then what will seal the deal is the personality of the challenger. In some cases the challenger never has a real chance like 1984. However in other elections the challenger gets a serious look.
GW Bush and Barack Obama were both vulnerable during their re-elections. In both cases the public had asked the question "should this person be re-elected?" and for a large enough segment the answer was "possibly not". But as people got to know their challenger, they went with the incumbent in part because of mistakes made by the challengers, strong campaigning on the part of the incumbent, but the incumbent in the end was more interesting. Kerry is a boring policy wonk and Romney is an out of touch rich guy.
