Jan. 24 (Bloomberg) -- The race for the Democratic presidential nomination is tightening as voters say they want both Hillary Clinton and Barack Obama on a national ticket, a Bloomberg/Los Angeles Times poll shows.

Clinton leads Obama, 42 percent to 33 percent, down from the 24-point advantage she held in early December. Three out of five supporters of each candidate say they would like Clinton or Obama, if nominated, to choose the other as a running mate.

Among Republicans, John McCain tops the field with 22 percent, followed closely by Mike Huckabee and Mitt Romney. The biggest change in the poll is the shift from former front-runner Rudy Giuliani, whose support plummets almost by half to 12 percent since a survey last month.

While the Democratic race is really down to two candidates and the Republican field remains ``wide open,'' the poll shows that no contender in either party can claim the title of front- runner, says Susan Pinkus, the Los Angeles Times polling director. ``It's anybody's guess who's going to win.''

Democratic voters are happiest with their choices, the Jan. 18-22 poll found. Three out of four say they are satisfied with the field, compared with a little more than half of Republicans. That satisfaction also shows up in hypothetical general-election matchups; the poll has Clinton and Obama beating every Republican with the exception of McCain, who rates a statistical tie with both.

Democrats

Former North Carolina Senator John Edwards, 54, trails well behind Obama and Clinton, pulling in 11 percent support. If Edwards were to drop out, more of his backers may head to Clinton than Obama, the poll shows.

As in past surveys, voters say they trust Clinton more on issues, while giving Obama higher marks for character. Almost half of respondents say Clinton, 60, a New York senator, would do the best job on the economy, compared with 27 percent who pick Obama, 46, an Illinois senator.

``She's been around long enough to know the ropes and how to get around Washington and get things done,'' says Eva Delashmet, 57, a poll respondent who runs a home-management business in Naples, Florida. Delashmet planned to cast an early ballot for Clinton yesterday ahead of her state's Jan. 29 primary.

Health Care

Clinton also leads when voters are asked about health care and foreign policy and is close behind Obama on the question of who can best deliver change, a central theme of the Illinois senator's campaign. Obama tops Clinton by 13 points on honesty and integrity. And by a margin of almost 2-to-1 Democratic voters in the poll say they care more about a new direction than experience.

``We need a change,'' says Bettie Garner, 53, an Arlington, Texas, resident who works in a residential community and cares for people with Alzheimer's disease.

Obama's support among various subgroups of Democrats has strengthened as his overall numbers rose; he is now the choice of 66 percent of black respondents, while Clinton pulls in 18 percent. That backing may be crucial as the candidates head to the Jan. 26 South Carolina primary and other contests in Southern states with large black populations.

The subject of race spilled into the campaign in the past two weeks. Even so, more than three out of five Democratic respondents say they don't think either Clinton or Obama is trying to use racial issues to win votes.

Shared Ticket

The survey finds that 62 percent of Democrats would like Clinton to pick Obama as her running mate if she is the nominee; 60 percent say they would want Obama to pick Clinton.

``You need to have complementary people,'' says Marian Dondero, 53, an elementary school administrator in the Philadelphia suburb of Wyncote, Pennsylvania, who plans to vote for Clinton. ``She's really intelligent and straightforward and she's a good problem solver. He lifts your imagination.''

Recent clashes between the candidates may dim the possibility of a shared ticket. During a Jan. 21 debate in South Carolina, the two battled over their past actions as lawyers, their votes as lawmakers and what they described as misrepresentations of their views by the other's campaign.

On the Republican side, Giuliani and McCain have switched places since the last Bloomberg/Times poll, conducted Nov. 30- Dec. 3. On the strength of his victories in New Hampshire and South Carolina primaries, McCain, 71, an Arizona senator, moves up from 11 percent support in December. Giuliani, 63, a former New York mayor, drops from 23 percent, and is counting on a win in Florida's primary to revive his candidacy.

McCain `Best' Offer

McCain is ``the best of what we have to offer,'' says Mike Weis, 44, a Long Island, New York, resident who installs high- end security systems. ``He's got a chance.''

Huckabee gets 18 percent support in the poll, while Romney pulls in 17 percent.

Each of the top candidates gets high marks from voters in different areas. McCain is far ahead of all of his rivals on foreign policy. While two-thirds of all respondents say they want the U.S. to pull troops out of Iraq within a year, 58 percent of Republicans say they should stay ``as long as it takes,'' the position adopted by McCain.

More surprisingly, 23 percent of respondents say McCain would do the best job handling immigration, an issue that has opened him up to criticism from Republicans who characterize his position as favoring amnesty for illegal aliens. McCain's closest rival on the question, Romney, got 14 percent. Almost one-fifth are undecided.

McCain also tops the field on the question of who will substantially change the way things are done in Washington, even though he has been in Congress for a quarter-century.

Social Issues

When it comes to social issues, Republicans look with the most trust to Huckabee, 52, a former Arkansas governor. Romney, 60, a former Massachusetts governor, gets the most credit for his ability to handle the economy, which Republican voters ranked as by far their most important issue.

By a 2-to-1 margin, Republican voters agree that whoever becomes the nominee should campaign on a platform of moving in a new direction, rather than continue with the policies of President George W. Bush.

The poll shows that Clinton and Obama would both beat Romney, Giuliani and Huckabee by margins of 10 points or more in theoretical general-election matchups. Obama and McCain almost split the vote in the poll, while Clinton had a 4-point edge over McCain, within the margin of error for the question.

The poll of 1,541 adults included 1,312 registered voters and had a margin of sampling error of plus or minus 3 percentage points for both groups. For the 532 Democratic primary voters, the margin is 4 points; for the 337 Republicans, it is 5 points.

To contact the reporter on this story: Kristin Jensen in Washington at kjensen@bloomberg.net

Last Updated: January 23, 2008 19:00 EST