Several weeks ago, speculation on the political aspects of a possible U.S. invasion of Iraq centered on whether doubts by members of both parties might prevent or delay an approval of authority for President Bush.

That almost certainly was somewhat misleading, since Congress, given a choice between standing up to a president on foreign policy or acquiescing in policies about which many have concerns, almost always chooses the latter course.

In any case, Bush ended the uncertainty with his forceful speech to the United Nations and by vowing to hold lawmakers’ feet to the fire on the issue.

While some congressional Democrats still would like to delay a vote until after the Nov. 5 elections and withhold authorization for an attack from any initial grant of authority, the ultimate outcome seems hardly in doubt.

In the end, Congress almost certainly will vote overwhelmingly to authorize Bush to proceed in all ways he finds necessary to force Iraq’s compliance with the United Nations’ directives it has flouted for many years. The vote seems likely to be more one-sided than the 1991 action backing the first President Bush’s efforts to expel Iraq from Kuwait.

There are several reasons.

First, there is no support, either in Congress or in the country at large, for Saddam Hussein, a brutal dictator who has killed thousands of his own people and remains a threat to the Middle East.

While some doubt how directly he threatens the United States and some question the wisdom of a pre-emptive U.S. strike, few members of Congress want to put themselves in the position of seeming to vote for the Iraqi dictator over Bush. Only liberal Democrats with safe districts may be willing to take that chance.

Second, lawmakers have to calculate that any effort to topple Hussein is likely to be successful. Though many Democrats survived politically after opposing the 1991 war, it may be no coincidence that the candidates on the party’s national tickets in subsequent national elections all supported it.

As was true after last year’s terrorist attacks, Democrats may conclude that the smartest politics, and the best thing for the country, is to back Bush. Besides, if any Iraqi mission goes amiss, Bush is likely to suffer politically, since it was his idea.

Third, lawmakers over the years rarely have been willing in the end to substitute their judgment or knowledge for that of a president. Even after the country turned against the Vietnam War, repeated efforts to end it by cutting off funds failed, though by increasingly close votes. Congress eventually voted to limit future U.S. troop commitments in the War Powers Act, but that has proved ineffectual in limiting future presidents.

Still, even a one-sided vote to back Bush on Iraq may be a somewhat misleading measure of his standing in Congress. In recent months, even Republicans have questioned, both publicly and privately, the way the president has treated lawmakers, both by withholding crucial information and for his inconsistent efforts to influence the legislative process.

As for the politics, Democrats who want to delay a vote may be lucky enough to be unsuccessful. No sooner had Bush derided the notion of delaying a congressional vote until the Security Council acts than Republicans began to raise Iraq in many close House and Senate races, putting critics very much on the defensive.

To be sure, some Democrats in close Midwest Senate races may prefer to avoid a vote forcing them to choose between Bush and their own strongest backers. But for most Democrats, the best thing may be for Congress to pass a resolution of support. Then, they can use the final three weeks before the Nov. 5 balloting to spotlight the very real differences between themselves and Republicans on many domestic issues, while noting they agree on the need to oust Saddam Hussein.