Now that Democrats have voted or caucused in three states in three different parts of the country, it appears there is one crucial voting bloc that will not support : older Americans.
Obama was able to overcome a consistent age gap in Iowa because of an unusually high turnout by young voters who supported him overwhelmingly. And he may be able to carry South Carolina, where roughly half the Democratic primary voters are expected to be African-American.
But Obama's weak performance so far among older voters substantially increases the odds against him scoring big victories in the slew of states voting on February 5th, "Super Duper Tuesday."
has dominated among voters of a "certain age."
In Iowa, Clinton grabbed 45 percent of the 65 and up while Obama took just 18 percent. In New Hampshire, she won 48 percent to 32 percent. Among voters 60 and older in Nevada, Clinton mopped up with a stunning 60 percent to Obama's 31 percent.
Nationally, Clinton led Obama 44 percent to 18 percent among voters over 65 in a CBS New/The New York Times poll taken January 9-12.
This could be Hillary Clinton's secret recipe for success. That's because older Americans turn out to vote.
Voters over 65 were a solid 22 percent of the Democratic primary electorate in Iowa.
But in Nevada, a dazzling 36 percent of the primary voters were over 60. Turnout for the caucuses was huge. Nearly a third of the state's registered Democrats participated. All Democrats, even the over-65 crowd, are unusually motivated this year - not just the young voters Obama has energized.
Clinton has solid support among other populations, especially women and voters down the income ladder. But Obama has had at least some success with those groups. In Iowa, he carried women 35 percent to 30. And voters earning less than $50,000 a year preferred Obama 34 percent to 32 percent.
Before real voters began casting real votes, it was natural to wonder if older Americans were more ready to consider a woman president or a black president. It appears that the answer is in and it is to Hillary Clinton's advantage.
In the CBS News/New York Times national poll, 94 percent of respondents said they were ready to vote for a black candidate for president. But when asked if "most people" they knew were ready to make the same choice, only 71 percent said yes.
When asked if the whole country was ready to elect a black president, just 54 percent said yes. By contrast, 65 percent said the country was ready to elect a woman president.
There is no reliable way to tell exactly what role race has played in the voting decision of older Americans. Older voters might also be expected to place a higher premium on experience. Whatever the reasons, the pattern of voting behavior so far is clear.
It is a pattern that could be a key to making Hillary Clinton the first female presidential nominee in American history.
By Dick Meyer