PARIS — President Barack Obama remains by far the most popular world leader among people in major Western nations and is the one political figure on whom people consistently pin their hopes in the economic crisis, according to new polls conducted for the International Herald Tribune.

About 80 percent of people in France, Germany, Italy and Spain have a positive view of Mr. Obama, a ratio that declines only slightly, to about 70 percent, in the other two countries surveyed, Britain and the United States. The only politician who comes close is Chancellor Angela Merkel of Germany, who gets a positive rating from two-thirds of those in Continental Europe but from only one-third of Britons and Americans.

The new survey, conducted by Harris International for the I.H.T. and the cable news channel France 24, reinforces the results of one conducted a month earlier showing that about half of those surveyed expressed the most confidence in Mr. Obama’s ability to solve the economic crisis, with Mrs. Merkel coming in second, at 22 percent.

The surveys found that a solid majority of people in the major Western democracies expect a rise in political extremism in their countries as a result of the economic crisis. Even in the United States and Italy, the two countries whose citizens are least likely to hold that view, fully 53 percent of those surveyed say more extremism is “certain to happen” or “probable” in the next three years.