When given the choice between McCain and Sen. Hillary Clinton, D-N.Y., when it comes to answering the sort of phone call featured in a Clinton TV campaign spot in which a White House phone rings at 3 a.m. amid a national emergency, 55 percent of respondents said McCain, while 37 percent preferred Clinton. Nine percent said they were unsure, the Zogby poll found.

Between McCain and Sen. Barack Obama, D-Ill., the Arizona senator led 56 percent, compared to Obama's 35 percent. Ten percent said they were unsure.

The poll found McCain, a self-described conservative, is preferred by 25 percent of the very liberal and 32 percent of mainline liberals over Clinton in this scenario. Meanwhile, 23 percent of the very liberal and 35 percent of mainline liberals prefer McCain over Obama.

Among conservatives, 15 percent said they would want Clinton to take the call, and 16 percent said they would rather have Obama answer.

The poll of 1,004 likely voters was conducted March 13-14. It has a margin of error of plus or minus 3.2 percentage points.