Vice President Dan Quayle, warmed by a new vote of confidence from President Bush, went about his normal duties and took in stride the fleeting possibility that he might have served as a temporary "acting president."

Quayle's spokesman Dave Beckwith said Quayle was "glad" when he was informed at dawn by White House chief of staff John Sununu that Bush would not have to undergo an electric shock treatment for his irregular heartbeat that would have required anesthesia.Facing that prospect, Bush ordered the proper papers prepared to permit a temporary transfer of presidential powers to Quayle under the 25th Amendment.

Bush's sudden hospitalization and the stark reality that Quayle might be forced into the presidency prompted speculation in political circles that Bush mighthave second thoughts on whether the 44-year-old vice president was capable of stepping in and performing the job.

The president, on his return to the White House from Bethesda Naval Hospital after a two-day stay, was unequivocal on the subject, telling reporters: "Hey, he has my full support, always has, and he's doing a first-class job."

At a news briefing, White House press secretary Marlin Fitzwater was asked if the president "has any reaction to all the reports that are now surfacing, questioning once again whether Quayle is fit to serve on the ticket."

"The vice president is doing a great job and he is very supportive during this situation, and we know he'd do a good job in whatever he is called upon to do," said Fitzwater.

But, polls taken since the president's illness indicate Americans are still unsure of Quayle's capabilities to run the country.

A USA Today poll of 611 adults, with a 4 percent margin of error, conducted Monday evening showed that while Quayle's popularity has increased - 43 percent approval, up from 19 percent in April - 51 percent say Quayle should be dumped from the 1992 Republican ticket.

In a Washington Post-ABC News poll of 505 people conducted Sunday, with a 5 percent margin of error, 57 percent said Quayle was not qualified to take over as president, up from 49 percent who felt that way in February.

A poll of 616 adult Americans conducted by CNN and Time magazine on April 24-25, before Bush was hospitalized, showed that 66 percent of those surveyed did not believe Quayle was qualified to be president now. And 67 percent said they would not vote for him if he were to become the Republican nominee in 1996, according to the poll, which had a 4 percent margin of error.

Beckwith bristled over questions surrounding Quayle's competence to step into the presidency. "With all due respect," he told United Press International, "there is nobody except a Democrat saying anything different. Why is it an issue?"