Even as the polls were tipping his way last week, President Carter was letting his campaign audiences know in increasingly strident terms how he sees the choice this Nov. 4.

Carter told a group of New Jersey labor leaders that this election represents one of the most important decisions of their lives.

"It's more important than the level, of your income. It's more important than the quality of house that you have. It's more important than which college you can send your children [to]. It's more important than the neighborhood where you and your wife might ultimately retire," the president said.

In case there was any lingering doubt as to how badly Carter wants to win reelection, he went on the next day to call the election "one of the most important decisions to be made in political history."

Throughout the campaign, Carter has been looking for ways to motivate Democrats who may be unenthusiastic about his administration to vote on election day instead of staying home.

In city after city, Carter has hammered away at the differences between himself and Ronald Reagan, seeking to frighten voters to the polls with his image of his Republican opponent. The most effective issue for Carter in this effort has been what the White House staff calls "war and peace" -- his implication that the chances of war would be increased if Reagan were elected. i

One of the questions the election will settle, Carter told a fund-raiser in Secaucus, N.J., is: "What will be done with nuclear weapons?" Reagan, Carter said, "advocates the possibility of a nuclear arms race."

On recent campaign trips Carter has more and more often used another rhetorical device designed to frighten Democrats (and independents) into the Carter column Nov. 4 Carter recalls to his audiences election day of 1968: if fewer Democrats had stayed home that day, he tells them, Richard M. Nixon would never have been president of the United States.

For anyone who doesn't fully understand what Carter has in mind when he mentions 1968, the president goes on to point out that there was a third-party candidate -- George C. Wallace -- who clouded the issue that year, too.

Carter's startling claim that Americans should care more which man they elect president than how much money they earn or what kind of home they have implicitly raises the war-and-peace issue in a new form. Only nuclear war, it would seem, could make his statement valid in an age which has seen the ability of presidents to affect the lives of their fellow citizens decline, overwhelmed by the size of the nation and the complexity of its problems.

It is also an example of how absorbed in -- some would say consumed by -- his reelection campaign Carter has become.

The president went on to appeal to the labor leaders to put at least 25,000 workers "out there in the streets, in the stores, talking to people and letting them know how crucial to the future of this country and to your state and your families this election is."

After all, he told them, "my election can be in your hands . . ."