(CNN) - One week after Hillary Clinton made a public show of unity with Barack Obama, a new survey suggests supporters of the New York senator are increasingly less likely to follow her lead.
A growing number of Clinton supporters say they may stay home in November instead of casting their ballot for Obama, a clear sign the party has yet to coalesce around the Illinois senator four weeks after the most prolonged and at times divisive primary race in modern American history came to a close.
According to a new survey from CNN and the Opinion Research Corporation, the number of Clinton supporters who plan to defect to John McCain's camp is down from one month ago, but in what could be an ominous sign for Obama as he seeks to unify the party, a growing number of them say they may not vote at all.
In a CNN/ORC survey conducted in early June, entirely before the New York senator officially ended her White House bid, 22 percent of Clinton supporters said they would not vote at all if Obama was the party's nominee. Now close to a third say they will stay home. In all, only 54 percent of Clinton backers say they plan on voting for Obama.
In another sign the wounds of the heated primary race have yet to heal, more than 4 in 10 registered Democrats - 43 percent - still say they would prefer Clinton to be the party's presidential nominee. That number is significantly higher than it was in early June, when only 35 percent of Democrats said they preferred the New York senator to lead the party's presidential ticket Then, Obama won 59 percent of support from registered Democrats, now he garners 5 points less.
By nearly any measure then, it's clear Clinton supporters remain wary of supporting the man who beat her.
"These things always take time to heal," CNN Senior Political Analyst Bill Schneider said. "I think Clinton's supporters are waiting to see if Sen. Obama will pick her as vice president. That would certainly be very healing to them."
But most political observers agree the prospects of an Obama-Clinton ticket remain dim, most notably because the New York senator remains a divisive figure in American politics and Obama's message of change threatens to be muddled by the 16 years Clinton has spent in Washington
But the question remains whether Obama can win enough Democrats without Clinton as his No. 2.
"If he doesn't pick her, a later stage of grief is depression and then acceptance," Schneider said. "In the end I expect Clinton supporters will accept Obama, because they will listen to Sen. Clinton who has said the stakes are too high for Democrats to sulk."
In the end, maybe more than four weeks is needed for many of Clinton's most devoted supporters to move past her loss, especially considering the primary campaign stretched more than 17 months.
"Many voters find it tough to immediately switch allegiances to a candidate that they once opposed, so they find a 'neutral' setting more comfortable for awhile," CNN Polling Director Keating Holland said. "If that's what is happening to the Clinton supporters who now say they plan to stay at home, Obama may have nothing to worry about. If not, there's a big chunk of the party base that Obama won't be able to count on in November."
While Clinton's stock among many Democrats remains high in the latest CNN/ORC poll, her husband's is decidedly lower since a year ago at this time.
Much has been made of Bill Clinton's role over the course of his wife's White House bid - the increasingly aggressive campaign style, the sharpened attacks leveled at Obama that some viewed as carrying racial overtones, and the outbursts at some reporters over what he viewed as unfair media coverage - and the former president increasingly came under fire from neutral Democrats and party elders concerned he was fracturing the party in an election cycle during which Democrats appear to hold the advantage in nearly every way.
And the former president clearly left a sour taste in the minds of some Americans - among all registered voters his approval rating is down 9 points in just over a year (60 percent to 51 percent.)
"Former presidents are supposed to be above politics, but Bill Clinton couldn't be above it in this campaign since his wife was a candidate for president," Schneider said. "But he was seen as too political. Democrats thought it was appropriate for him to support his wife but not appropriate to get overly critical of Obama."
So can Clinton, who left office eight years ago with approval ratings well over 60 percent, repair his image with most Americans?
"He needs to show he's gotten over it," Schneider said.