Sen. Bernie Sanders of Vermont has a 9-point lead over former Secretary of State Hillary Rodham Clinton in the early state of New Hampshire, according to a new poll that shows Mrs. Clinton falling further behind should Vice President Joseph R. Biden enter the race for the 2016 Democratic presidential nomination.
Mr. Sanders led Mrs. Clinton by 9 points, 48 percent to 39 percent, according to the NBC News/Wall Street Journal/Marist poll — similar to the 49 percent to 38 percent lead he had a month ago.
When Mr. Biden was added to the contest, Mr. Sanders was at 42 percent, followed by Mrs. Clinton at 28 percent and Mr. Biden at 18 percent.
Mrs. Clinton did have an 11-point, 47 percent to 36 percent lead over Mr. Sanders in an NBC/WSJ/Marist poll on Iowa — essentially unchanged from a month ago, when she led by an 11-point, 48 percent to 37 percent margin.
But once again, Mr. Biden’s addition to the field hurt her position. With the vice president added, Mrs. Clinton was at 33 percent, followed by Mr. Sanders at 28 percent and Mr. Biden at 22 percent.
Mr. Biden has not yet announced his 2016 plans. The first Democratic debate is on Tues., Oct. 13.
The polls were conducted Sept. 23-30. In Iowa, 348 Democratic caucus-goers were surveyed at a margin of error of plus or minus 5.3 percentage points; and in New Hampshire, 404 Democratic voters were surveyed at a margin of error of plus or minus 4 percentage points.