A new poll finds Clinton running neck-and-neck with some of her Republican rivals in Virginia. (Jim Cole/AP)

With the official launch of her presidential campaign, Hillary Rodham Clinton’s support in Virginia has weakened as her Republican challengers gain strength.

Former Florida governor Jeb Bush, New Jersey Gov. Chris Christie, Kentucky Sen. Rand Paul and Florida Sen. Marco Rubio are all neck-and-neck with the Democratic frontrunner in a new poll of Virginia voters from the Wason Center at Christopher Newport University. Only against Texas Sen. Ted Cruz and Wisconsin Gov. Scott Walker does Clinton lead by more than four percentage points. Bush leads her by two points in the poll.

The results show a downward slide for Clinton since the university’s last poll of the swing state in February, when she bested all her likely rivals.

“In the face of a barrage of attacks from her real and potential Republican challengers, Hillary Clinton’s once formidable position has weakened, as we knew it would,” Tom Kramer, assistant director of the Wason Center for Public Policy, said in a statement.

In the Democratic primary, more gentle jabs at Clinton have not had an impact in the commonwealth. She continues to dominate among Democrats with 80 percent of the vote. Former Virginia senator Jim Webb takes 6 percent of the vote and former Maryland governor Martin O’Malley just 1 percent.

The Republican primary field is far more fractured. Bush and Rubio lead, followed by a three-way tie between Christie, Paul and Walker. But no candidate gets more than 17 percent of the vote.

The former secretary of state is both liked and disliked more than any other contender from either party, with a 44 percent favorability and 52 percent unfavorability rating. Only Vice President Biden is as well-known, and he is viewed less favorably, with 35 percent positive and 57 percent negative responses. More than half of voters say they don’t know O’Malley or Walker. A third don’t know Webb, who left office in 2013; those that do are evenly split.

The poll was taken from April 13 to 24, with 388 landline and 270 cellphone interviews of registered Virginia voters. The margin of error is 4.6 percent.