She’s behind Barack Obama in popular votes, delegates and overall wins, but Hillary Rodham Clinton‘s backers have found a new way to claim their candidate is on top – Electoral College votes.

It’s the latest case Clinton boosters are making for why she is a stronger general-election candidate than Obama – and quickly drew return fire from the Obama campaign, which charged that she keeps changing the ground rules.

Clinton spokesman Phil Singer touted an idea yesterday first floated by supporter Indiana Sen. Evan Bayh on CNN on Sunday, in which he argued that “who carried the states with the most Electoral College votes is an important factor to consider because ultimately, that’s how we choose the president of the United States.”

Bayh was referring to factors that superdelegates – who could determine the nominee – should consider when deciding whom to back. “I think Evan Bayh makes a compelling point, which is that Sen. Clinton has won and performed well in a number of the states that are going to be vital and will be general election battle grounds,” he said.

By Electoral College votes in states won by each candidate, Clinton leads Obama, 219-202.

Singer said the candidate who “is going to be best able to accumulate the requisite 270 electoral votes” should be a deciding factor in determining the nominee.

Obama spokesman Tommy Vietor shot back, “With the Clinton campaign, the goalposts for winning the nomination seem to be in a perpetual state of motion – but the fact is, this is a race for delegates.”

Vietor added, “The notion that we’re not going to win states like New York and California as the nominee is ludicrous.”

Meanwhile, Clinton aides yesterday said she may have “misspoke” when she said she landed “under sniper fire” in a trip to Bosnia in 1996. Clinton spokesman Howard Wolfson said that there had been reports of nearby sniper fire, but that no shots were actually taken at the aircraft as it landed.

Also yesterday, Wolfson said the campaign hasn’t decided whether to participate in a CBS debate to which Obama has committed in North Carolina on April 19.

maggie.haberman@nypost.com