Americans plan to spend most in 5 years this Christmas

Americans plan to spend more on gifts this Christmas than in any holiday season in the past five years as economic optimism hits a post-recession high, according to the CNBC All-America Economic Survey.

The average American plans to spend $765 this year, up 12 percent versus last year, and about 6.5 percent higher than the average across the survey's nine-year history. Behind the Yuletide cheer is an improved outlook for expected home values, wage gains and stocks—all three are at or above their highest levels since the 2008 recession.

The poll of 806 Americans nationwide was conducted by the Republican/Democrat polling team of Hart-McInturff over Thanksgiving weekend and has a margin of error of plus or minus 3.5 percentage points.

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Sentiment has popped in the survey before only to retrace its gains, so the overarching question is whether it will stick this time. One reason for optimism is that the current numbers eclipse the old post-recession highs and have begun to approach precrisis levels.

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For example, 26 percent said the economy is excellent or good, with the 8-point gain the best on record and optimism equal with that of December 2007.

A full 94 percent expect their home value to increase or stay the same, with an average expected gain of 2.8 percent, the best since June 2013. And average expected wage gains hit 5.3 percent, near their prerecession levels even though a few responses drove the wage gains higher.

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It's possible, however, that several temporary factors are driving the current surge in optimism and these may or may not have staying power. Lower gas prices have led to expected inflation of just 2 percent, the lowest on record for the survey.

Many economists have pointed to plunging gas prices as a catalyst for increased holiday spending, and that may yet come to pass. But only 8 percent of shoppers who plan to spend more on holiday gifts this year cite lower gas prices as the reason, compared with a third who cite higher incomes.

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In the wake of the GOP victory in the Senate, Republican optimism over the outlook for the economy rose to the highest level since December 2009. However, Republicans still are net pessimistic on the economic outlook compared to Democrats who are net positive.

Higher stock prices also seem to be buoying American spirits, with 41 percent saying now is a good time to invest, a 10-point gain. Better sentiment about the market goes beyond just the wealthy or those who are heavily invested in stocks. Blue collar workers and those with incomes between $50,000 and $70,000 all registered their most upbeat views on stocks since 2008. And for the first time since 2008, women are net positive about stocks (that is, those saying it's a good time to invest minus those saying it's a bad time.) In general, women have been more pessimistic on equities than men during the recession and expansion.

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Optimism over stock prices appears to be highly correlated with year-over-year changes in the Dow, so a decline in stock prices would knock that leg of the stool out.