The 20% number that I pulled out of my hat turns out to be a little low. A new AP poll
says that 27% of likely voters are "persuadable".
Overall, the poll found that among registered voters, 47 percent say they will vote for the president and 44 percent for Romney, a difference that is not statistically significant.
Those totals include soft support, though, meaning people who lean toward a candidate as well as those who said they could change their minds before November. The poll showed that these persuadable voters are equally apt to lean toward Obama, Romney, or neither, with about one-third of them in each camp.
The survey also showed that these voters are more likely than others to say they distrust both Romney and Obama on the major issues. They are far more likely to think the outcome of the election won't make a big difference on the economy, unemployment, the federal budget deficit or health care.
Party politics and wedge issues have dubious weight with this group. The poll found more independents fall into this category than partisans. The partisans who are persuadable are more likely to be in the ideological middle than either liberal Democrats or conservative Republicans. Seventeen percent of persuadables say they consider themselves supporters of the tea party.
The poll also found that demographically, they are more likely to be members of Generation X (between the ages of 30 and 49) than other registered voters. Many, 71 percent, have not graduated college. They are a bit more likely to have lower incomes than all registered voters. Fifty-two percent of persuadables have incomes below $50,000, compared with 44 percent of all voters.
On other characteristics — gender, religious preference and race — they're split similarly to other registered voters.
Of course this doesn't address the subject of the OP, but I thought it was an interesting breakdown. Though I don't see how any tea partiers can be persuaded to vote for Obama...more likely they need Romney to convince them they shouldn't just stay home.