The old theater adage demands that if you show a pistol in Act 1, you better fire the gun in Act 3. That same wisdom applies to politics.
The voters have been pointing a symbolic gun at the Republican regime in Washington for many months now. All that remains for Election Day is to pull the trigger.
When you examine the latest round of pre-election polls, what is striking is the stability of public attitudes over the preceding months. In this week's Washington Post-ABC News poll, for example, President Bush has a job approval score of 39 percent, with 60 percent disapproving. Eleven months earlier, in November of 2005, the scores were identical.
In between, Bush got up as high as 47 percent and fell as low as 33 percent. But at no time did more Americans approve of his job performance than disapproved.
The public has shown similar consistency with party support for Congress. In the latest poll, Democrats lead Republicans, 54 percent to 41 percent among registered voters. In November 2005, the Democrats led 52 percent to 37 percent. The margins are almost identical.
To take one more example, look at the broad question of the overall direction of the nation - right path or wrong track. In this latest poll, by a margin of 66 percent to 32 percent, people said, "wrong track." Last November, the comparable numbers were 68 percent and 30 percent.
What all this suggests is a settled judgment on the part of the majority of Americans that the current leadership of the nation is not doing the job people expect. This is the government the people chose in 2004, but now they are showing clear signs of buyer's remorse.
The disillusionment is not the product of the Foley scandal - which is shifting few votes as far as I can judge. And it also reflects more than the continuing spate of bad news from Iraq, though that has had a large effect on public opinion.
What is driving public opinion is an overall impression that those in office - meaning mainly Republicans - have let things slide out of control and need to be relieved.
What voters may not know is that the same judgment has been reached by a significant number of people who are part of - or close to - the Republican majority. If I have heard it once, I have heard it a dozen times: Major Republican figures, including top officials of several past GOP administrations and Congresses, say, "We deserve to lose this election."
The failure is most evident at the Capitol end of Pennsylvania Avenue. The one measure of opinion that has shifted significantly in the past year is the public judgment on Congress. In the latest poll, it is negative by a 66 percent to 32 percent margin. Last November the gap was much smaller, with 59 percent disapproving and 37 percent approving.
The failure of this past Congress to act meaningfully on immigration, energy, health care or other vital needs has left the public frustrated - and the members of Congress feeling embattled.
But there is also a palpable sense of weariness in the executive branch, and a need for relief there as well.
Fortunately, the voters have the power - if they pull the trigger on Election Day - to create a new plot for the Washington drama. This election campaign has been a learning experience for candidates of both parties, incumbents and challengers alike. They have been bombarded with messages from their constituents, telling them that the public is tired of the partisan bickering, tired of the gridlock, and eager to elect people who will focus on the real problems and work together to find solutions.
If that lesson is reinforced by the election results, Washington will change. Congress will be run by people who talk with each other, across party lines. And even the White House may learn that it needs to end its isolation and engage more broadly, at home and abroad, if it is to salvage some substantial accomplishments from Bush's final two years in office.
That kind of fundamental change in the political environment is possible - indeed, it is imminent and will be welcomed. But it will happen only if voters pull the trigger. Elections do matter, and this one matters more than most.
l R.W. "Johnny" Apple, the New York Times political reporter who died last week, set the standard for our business for all of his working life. He covered the beat - and wined and dined - better than anyone else, and the joyfulness of his life was infectious.