A majority of Americans believe the United States should attack Iraq if U.S. hostages are mistreated by President Saddam Hussein and nearly as many favor military action if the economic boycott fails, according to a new ABC News poll.

In important ways, the survey found Americans increasingly willing to give President Bush a cautious green light to turn up the heat on Saddam, even if the result is war.

More than half of those interviewed -- 51 percent -- said U.S. forces should attack Iraq if the economic boycott fails, up from 46 percent in a Washington Post-ABC News survey conducted last month.

If war does break out, 61 percent say the United States should bomb Iraq even if U.S. hostages might be killed, up from 51 percent just a month ago. Of those questioned, 56 percent said the United States should attack Iraq if American hostages are mistreated, and 41 percent supported an attack even if hostages' lives might be lost.

The survey also found that about seven out of 10 Americans continue to believe that the United States is headed toward a war with Iraq, unchanged from last month's survey but up significantly from polls conducted immediately after Bush dispatched troops to the Persian Gulf eight weeks ago.

But more than two out of three persons questioned also said they wanted Bush to get congressional permission before going to war. A plurality said they would support the president if Bush believed there wasn't time to notify Congress.

Interviews with 1,015 randomly selected Americans conducted Nov. 2-4 found little change during recent weeks in public support for the continuing U.S. presence in the Middle East. Margin of sampling error for the overall results is plus or minus 3 percentage points.

In the most recent survey, 65 percent questioned said they approved of the way Bush was handling the crisis in the gulf, unchanged from the October poll but still nine points below his September peak.