President Obama appears to be widening his lead against all Republican presidential hopefuls, including Mitt Romney, among voters in the swing state of Virginia, according to a new poll.

President Barack Obama s (AP Photo/Pablo Martinez Monsivais)

The Quinnipiac University poll released Tuesday shows Obama’s approval rating sits at 51 percent. Forty nine percent of those polled say he deserves to be re-elected.

“President Barack Obama has opened up some daylight in Virginia against his Republican challengers,” said Peter A. Brown, assistant director of the Quinnipiac University Polling Institute. “His margin over Romney, in the state where Obama has been struggling after his win in 2008, compares to a slight 47-43 percent lead in February.”

Even adding Bob McDonnell, the popular Virginia governor, to the GOP ticket as vice president does not help the Republicans carry the state, according to the poll. In a matchup of Obama and Vice President Joe Biden against Romney and McDonnell, the Democrats win, 50 percent to 43 percent.

“There has been speculation about Gov. Bob McDonnell being a possible choice for vice president by the eventual GOP nominee,” Brown said. “What this Quinnipiac University survey finds is that despite the governor’s approval ratings with Virginia voters, he does not appear to help give the GOP the state’s electoral votes.”

Obama, the first Democratic president to win Virginia in 44 years, is trying to repeat his victory. He has campaign offices and staffers across the state, including in Northern Virginia, while no GOP hopeful has established much of a presence in the state so far.

The president leads former Pennsylvania Sen. Rick Santorum 49 percent to 40 percent; former House speaker Newt Gingrich, 54 percent to 35 percent; and Rep. Ron Paul (Texas) 49 percent to 39 percent.

Romney easily won Virginia’s primary this month after Gingrich and Santorum failed to qualify, but he is still struggling to win strong support from Republicans nationwide.

In Virginia’s closely watched U.S. Senate race, likely nominees George Allen (R) and Tim Kaine (D) remained tied, as they have been in many previous polls. Eight months before Election Day, Allen received support from 44 percent of those questioned, while Kaine received the backing of 47 percent.

The race, which will fill the seat of retiring Sen. Jim Webb (D), is expected to be one of the most competitive in the nation, and could help determine which party controls the U.S. Senate.

“Virginia’s U.S. Senate race has been too-close-to-call from the get-go,” Brown said. “It remains a squeaker and is likely to remain that way until the November election. An Obama victory in the presidential race would help Kaine, while if the Republican carries the state in November that would help Allen.”

Former governor Tim Kaine, left, and former senator George Allen, right, (AP Photo/Steve Helber)

In September, a Quinnipiac poll showed Allen at 45 percent and Kaine at 44 percent in Virginia. In October, another poll showed Allen had 44 percent and Kaine 45 percent. In December, a poll showed Allen had 44 percent and Kaine 42 percent. Last month, Allen received 44 percent and Kaine received 45 percent. All the results are well within the polls’ margin of error.

The Quinnipiac poll was conducted by live interviewers with registered voters on land lines and cell phones. The university releases periodic voter surveys of office holders, candidates and issues in Connecticut, New York, New York City, New Jersey, Pennsylvania, Ohio and Florida. Last year, it added Virginia, increasingly considered a swing election state.

For this poll, Quinnipiac University surveyed 1,034 registered voters March 13-18 with a margin of error of plus or minus 3.1 percentage points.

On Wednesday, the university will release the second part of its poll.

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