CAMDEN, New Jersey (Reuters) - Democrats running for governor in New Jersey and Virginia face possible defeat in November, despite strong showings by President Barack Obama in those states last year, in elections that could render the first judgments on the Obama presidency.

New Jersey Governor Jon Corzine delivers his opening remarks at a luncheon hosted by Harvard University's John F. Kennedy School of Government in New York February 19, 2009. REUTERS/Chip East

New Jersey Governor Jon Corzine, a close Obama ally, is struggling to win re-election in the face of a strong challenge by Republican Christopher Christie.

The Obama administration has turned out in support of Corzine, a wealthy former Goldman Sachs executive.

At a rally in Atlantic City this week, Vice President Joe Biden said it was “critically important” that Corzine is re-elected.

The Corzine campaign adapted the popular Obama slogan, hanging a banner next to Biden reading: “Yes we can -- again.

In Virginia, the only other U.S. state with a gubernatorial contest this year, Democrat Creigh Deeds has been losing so much ground in the polls to Republican Bob McDonnell that he has blamed the Obama administration’s $787 economic stimulus plan for his low popularity.

A Washington Post poll published on Friday gave McDonnell a commanding lead of 53 percent to 44 percent, with less than a month to go until election day.

“Frankly, a lot of what’s going on in Washington has made it very tough,” Deeds told Politico newspaper. “We had a very tough August because people were just uncomfortable with the spending.”

The Virginia race, where incumbent Democratic Governor Tim Kaine cannot run because of term limits, is more likely to be decided on national issues such as the economy and healthcare, said Larry Sabato, director of the Center for Politics at the University of Virginia.

A recent survey showed many voters in Virginia, where Obama won by 6 percentage points, expect taxes to rise as a result of a U.S. healthcare overhaul being considered in Congress.

Biden campaigned for Deeds this week in Virginia and the Democratic National Committee allocated another $1 million for his campaign. Democrats were waiting to see if Obama would make another appearance on Deeds’ behalf.

The race in heavily Democratic New Jersey reflects more the struggles of an unpopular incumbent than the national political mood, and will be decided on Corzine’s handling of such issues as the state’s high property taxes, analysts said.

Corzine has lagged in polls, sometimes by double digits, for months in a state that Obama won by 15 points and where the legislature is controlled by Democrats. The race has tightened up in recent weeks.

Corzine has tried to link Christie, a former U.S. Attorney with a successful record prosecuting corrupt public officials and suspected terrorists, to former President George W. Bush, whose market deregulation Corzine blames for the nation’s financial crisis.

“We went through Bush-whacking for eight years, and we have got a lot of work to do,” Corzine said. “We shouldn’t be turning the keys to the state house over to the people who wrecked the economy.”

Corzine has spent freely, having raised $16.8 million, $15.6 million of which came from his own pocket, while Christie has raised $9.6 million, official figures show.

The race has been so negative that Corzine ran a TV ad this week that appeared to mock the portly Christie for his weight.

“Corzine is in trouble,” said Maurice Carroll, director of the Quinnipiac University Polling Institute. Its polls show Christie leading by 7 to 12 points since the start of 2009.

Carroll attributed Corzine’s troubles in large part to New Jersey’s economy, where unemployment stood at 9.5 percent in August, equal to the current national rate but higher than in neighboring New York and Pennsylvania.

Corzine should be doing better because the anti-incumbent vote is split between Christie and an unexpectedly strong showing by third-party challenger Chris Daggett, who has been polled up to 13 percent in recent weeks, Carroll said.

In addition, the governor is sometimes described as lacking the common touch. “He’s not a convivial guy,” Carroll said.

Christie has won support outside of traditional Republican circles, such as the endorsement of the New Jersey Environmental Federation which is backing a Republican for statewide office for the first time.

Christie, who is running on a platform of lower state spending and tax cuts, dismissed his shrinking lead as part of the process.

“This is a natural tightening of the race that happens when people start locking in,” he said, adding that polls show his candidacy is very much alive in a state that has not elected a Republican governor since Christine Todd Whitman in 1994, recently abolished the death penalty and passed a civil unions law for same-sex couples.

“I should be dead and buried by now,” Christie said.

Democrats currently hold 28 governorships in the 50 states, while Republicans have 22.