WASHINGTON ( CNN ) -- Sen. Hillary Clinton of New York retains her position firmly at the front of the pack of Democratic presidential candidates , with a poll Thursday giving her 44 percent of the vote , nearly double the 24 percent garnered by the next-closest candidate , Sen. Barack Obama of Illinois . Former Sen. John Edwards of North Carolina was favored by 16 percent of the 458 registered voters who described themselves as Democrats or as independents who lean Democratic . New Mexico Gov . Bill Richardson followed with 5 percent , Sen. Joe Biden of Delaware attracted 3 percent and Rep. Dennis Kucinich of Ohio won 2 percent . Sen. Chris Dodd of Connecticut and former Sen. Mike Gravel of Alaska each attracted less than one half of one percent . While Clinton appear to be firmly entrenched as the front-runner , there is one important warning sign for the Clinton campaign . Among Democrats who did not graduate from college , she leads Obama by 26 points , but among Democrats with a college degree , Clinton has only a three-point edge . Turnout is much higher among college graduates , particularly in the primary season , so the Clinton camp may have to work harder to turn her lead in the polls into victory at the ballot box . A Washington Post/ABC News poll of Iowa voters released on August 3 had Clinton , Obama and Edwards in a virtual tie in that key early caucus state . Obama led with 27 percent , while Clinton and Edwards both had 26 percent . The CNN/Opinion Research poll , which had a sampling error of plus-or-minus 4.5 points , was conducted August 6-8 and involved telephone interviews with 1,029 adults . Since June , no candidate 's support has changed by more than one point . E-mail to a friend . CNN Polling Director Keating Holland contributed to this report .
Sen. Hillary Clinton at 44 percent leads Democratic presidential nominees . The poll was conducted from June 30 to July 1 among 1,501 registered voters and has a margin of error of plus or minus 3 percentage points. Clinton only has a 3-point lead over Obama among college graduates .