While nearly half of Americans don't have enough money saved to cover emergencies, one-quarter don't have any money saved, according to Bankrate.com's Financial Security Index survey.The general rule of thumb is to have enough cash saved to cover at least six months of expenses.However, only 25 percent of Americans have saved that amount and 17 percent have three to five months' expenses saved, while 28 percent have no emergency savings and 21 percent have less than three months' expenses saved.

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Those earning more than $75,000 annually have higher odds of saving six months of expenses. Only 9 percent of these high earners don't have emergency savings versus 52 percent of those earning less than $30,000.Among retirees, 41 percent have enough money saved to cover at least six months' expenses, while 26 percent have less than six months' expenses saved and 18 percent have no savings.In addition, 41 percent of college graduates report having emergency savings compared with 14 percent of those with a high school education.According to race, 23 percent of white Americans have no emergency savings compared with 38 percent of nonwhite individuals.Further, 28 percent of Democrats and 31 percent of Independents have no emergency savings versus 19 percent of Republicans."Incomes are largely stagnant, so it's difficult for people to make significant headway on savings when household expenses are creeping higher but incomes are not," Greg McBride, senior financial analyst for Bankrate.com, tells CNNMoney. "Prolonged unemployment has also depleted the savings of many people who at one time had a more appropriate cushion."The biggest barrier to saving is not being in the habit of saving," McBride says. "By establishing that habit, even if an unplanned expense comes up and wipes out what you've accumulated, you're only one paycheck away from restarting the saving process."The telephone survey was conducted June 7 through June 10 among 1,000 U.S. adults.

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