WASHINGTON (Reuters) - Democrat Barack Obama has a 4-point national lead over Republican John McCain as they head into the final week of the presidential campaign, according to a Reuters/C-SPAN/Zogby poll released on Tuesday.
Obama leads McCain by 49 percent to 45 percent among likely voters in the three-day national tracking poll, a slight dip from his 5-point advantage on Monday. The telephone poll has a margin of error of 2.9 percentage points.
McCain solidified his support among white and male voters but Obama retained double-digit leads among women and independent voters -- two key swing blocs in the November 4 election.
Obama had a strong single day of polling on Monday, pollster John Zogby said, and still holds a significant edge among Hispanics and Catholics, two groups who gave a boost to Republican President George W. Bush’s re-election win in 2004.
“With seven days to go in this race, McCain is still not where he needs to be with some key groups and he is running out of time,” Zogby said.
McCain, a veteran Arizona senator, has sliced Obama’s 12-point advantage by more than half in the last five days but he has not been able to break through the 45 percent support mark.
When the national tracking poll debuted on October 6, Obama led by 3 points, 48 percent to 45 percent. In the ensuing three weeks, McCain’s support has not been higher than 45 percent and Obama’s support has not been lower than 48 percent.
McCain has struggled in recent weeks to overcome Obama’s lead in national polls and to beat back a strong challenge from the first-term Illinois senator in about a dozen states won by Bush in 2004.
The swirling economic crisis helped emphasize Obama’s perceived strength on the issue, while a series of debates and Obama’s huge advantage in paid advertising in battleground states have also paid dividends.
Obama leads among all age groups except those between 30 and 49. He also leads among self-described blue-collar workers and those who have a member of the military in their family.
Obama also has done a better job of reaching across the ideological divide, winning one of every five conservative voters while McCain captures just 8 percent of self-described liberals, the poll found.
Independent Ralph Nader and Libertarian Bob Barr both received support from 1 percent of those polled nationally. Three percent said they remain undecided in the race.
The rolling tracking poll, taken Saturday through Monday, surveyed 1,202 likely voters in the presidential election. In a tracking poll, the most recent day’s results are added, while the oldest day’s results are dropped to monitor changing momentum.
The U.S. president is determined by who wins the Electoral College, which has 538 members apportioned by population in each state and the District of Columbia. Electoral votes are allotted on a winner-take-all basis in all but two states, which divide them by congressional district.
Editing by John O'Callaghan