Mauricio Lima for The New York Times

An image of President Hamid Karzai of Afghanistan in Kabul. He has not endorsed a successor.

KABUL, Afghanistan — In the 12 years since the United States helped oust the Taliban, Afghanistan has held four national elections. But Afghans are only now experiencing a phenomenon that has been upending conventional wisdom in more established democracies for decades: polling.

Three recent polls are giving Afghans a crash course in front-runners, horse-race coverage and candidates who eagerly dismiss any numbers that do not put them out front, topics familiar to Americans.

With the focus on fighting a war and rebuilding the country, there has been little publicly available polling done here for the two presidential and two parliamentary elections.

But now, before the presidential vote in April, Afghans are finding out which politicians have popular appeal ahead of the voting. How the information plays out remains to be seen, but it appears that Afghans — and the Western diplomats who are watching the campaign — would do well to heed an axiom of electoral politics: Do not trust the conventional wisdom.

Exhibit A appears to be the ability of President Hamid Karzai to influence the election. The widely held view in Kabul is that the candidate Mr. Karzai decides to back will be favored to win. As the sole elected leader in Afghan history, he is uniquely influential in a country where politics center on personalities, not political parties. At the same time, he controls the machinery of the state — the police, a growing bureaucracy, even the schools.

Most of the candidates appear to believe they need his support. Of the 11 men currently running, 10 have sought his blessing and support. But Mr. Karzai has yet to endorse any of them.

Even if he does, a poll conducted for the State Department by Glevum Associates, a research company based in Washington, indicates that the ability to influence voters simply by endorsing a candidate may be far more limited than most here believe.

Among the 2,148 likely voters surveyed by Glevum, 85 percent said they would not be swayed if Mr. Karzai decided to endorse a candidate or that it would not matter. The poll, conducted through face-to-face interviews and obtained ahead of its release on Sunday, has a margin of sampling error of plus or minus about two percentage points.

The poll results did not offer a clear sense of what accounted for Mr. Karzai's apparently limited influence. In many respects, those polled seemed to want a candidate much like Mr. Karzai: 61 percent would vote for someone who wanted to open talks with the Taliban, 51 percent thought it was important to have good relations with Pakistan and 71 percent wanted positive relations with the United States, as the Afghan leader says he does.

Yet his refusal to sign a deal that would keep American and European troops here beyond next year did not appear entirely unpopular, according to the poll. Only 40 percent of those surveyed said it was important that candidates wanted to keep foreign forces here after 2014.

Nearly 90 percent said they would not vote for a candidate with a history of corruption. But almost every candidate has faced allegations of graft, and the Afghan government is considered among the world's most corrupt.

Aimal Faizi, a spokesman for the president, said neither he nor Mr. Karzai had seen the poll. But "these polls are a new experience for Afghans," he said. "People are suspicious about why they are being done, about the possible motivations behind them."

Mr. Karzai has no plans to endorse any candidate, Mr. Faizi said, adding that the president wanted only to see a peaceful election "that is free of influence from the government — and interference from outside of Afghanistan, as well."

Mr. Karzai is particularly fearful of interference from the United States, which he believes tried to unseat him in the 2009 elections.

American officials insist that their sole intention is to help Afghanistan, not get involved in its politics. The poll was intended "to help promote inclusive, credible, and transparent elections in Afghanistan," the United States Embassy in Kabul said in a statement.