By DAVID LAUTER

Tribune News Service

WASHINGTON -- Perhaps it's just holiday cheer, but a few weeks after his party suffered painful losses in the midterm election, President Barack Obama is ending 2014 with his highest approval ratings of the year.

The evidence comes from new polls that show not only rising approval of Obama's performance in office, but also a warming trend in Americans' perception of the economy.

It's way too soon to claim a significant shift. The evidence for more than a year has shown the vast majority of Americans have strongly held views about Obama and that, as a result, changes in his approval ratings don't last. His ratings have been stuck at a tepid level through most of 2014.

But there are a couple of reasons to think the latest upswing might prove to be the beginning of something lasting.

First, the numbers: A CNN/ORC poll released Tuesday showed 48 percent of Americans approved of Obama's job performance. Although that still leaves him somewhat underwater, it's a 20-month high and up 4 percentage points from the previous month.

Similarly, Gallup's weekly tracking poll put Obama's approval at 45 percent through Sunday, the highest since May. Gallup's more volatile three-day average had Obama at 47 percent during the weekend, the highest level of the year.

Three factors seem to be bolstering Obama's ratings and could carry over into the new year.

The most important is the economy, which, except in cases of large wars or scandals, usually exerts the strongest pull on a president's ratings.

Recent economic news has been good, capped by Tuesday's report the economy's growth rate in the third quarter reached 5 percent.

For more than a year, as the economy has warmed, political analysts have wondered why Obama wasn't getting more credit.

One simple explanation is lag time -- after a deep recession, history suggests the public needs many months of solid economic growth to feel better about the economy and political leaders.

Now, that shift in public opinion might be taking place. The CNN/ORC poll, for example, showed 51 percent of Americans said they had a positive view of the economy, compared with 49 percent who had a negative view. That was the first time a majority in the poll had been positive about the economy in seven years, and a big jump from 38 percent in October.

Other polls have found smaller, though still notable, improvements in how Americans view the economy. Typically, such a shift benefits the incumbent.

A second factor might be the effect of some of Obama's policy decisions. His approval rating among Latinos, for example, moved sharply upward after his announcement last month the administration would seek to shield from deportation several million immigrants in the U.S. without legal authorization.

Although many Republicans have denounced the immigration decision, the impact on public opinion was almost all on the plus side for Obama, presumably because the vast majority of those who disapprove already had negative views of his presidency.

Finally, Obama has been plagued all year by a sense, even among those who tend to support him, that he is too passive and not a strong leader. The president's recent spate of executive actions on a broad range of issues, including climate change and relations with Cuba, along with immigration, could be combating that image.

Those factors -- particularly the economy -- could benefit Obama more in the year to come. That's by no means certain. But if it happens, rising poll numbers for the incumbent would significantly help the Democratic presidential candidate in the 2016 election.

The CNN/ORC poll interviewed 1,011 adult Americans on Thursday through Sunday; it has a margin of error of plus or minus 3 percentage points. The Gallup presidential approval numbers are based on approximately 1,500 interviews every three days; that poll has a margin of error of plus or minus 3 percentage points.