A poll by Quinnipiac University in Connecticut finds the numbers virtually unchanged since April 8, when a surge by Obama stopped.
Clinton leads Obama, 51 percent to 44 percent, with a sampling errof of plus or minus 3.1 percentage points in interviews with 1,027 likely Pennsylvania Democratic voters contacted by telephone from Friday through Sunday.
A poll by Boston-based Suffolk University has a slightly wider spread in the numbers -- 52 percent for Clinton to 42 percent for Obama.
That poll was conducted by telephone on Saturday and Sunday among 600 likely Democratic voters in Pennsylvania. The margin of sampling error there was plus or minus 4 percentage points.
