By Edward Epstein, Joseph J. Schatz and Molly K. Hooper, CQ Staff

Hillary Rodham Clinton may be trying to make it clear she wants all her delegates to get behind Barack Obama , but many still hadn’t gotten the message by Monday.

“I’m voting for Hillary on Wednesday,’’ Christopher Nichols, a Clinton delegate from Menlo Park, Calif., said regarding the formal roll call scheduled for Wednesday night at the Democratic National Convention. “What I do in November remains to be seen. I have a lot of questions about Obama’s past associations. I don’t feel like I know who Barack Obama is.’’

Such attitudes could spell trouble for the ticket of Sen. Obama, D-Ill., and Sen. Joseph R. Biden Jr. , D-Del. A new Gallup Poll found that while 47 percent of Clinton backers say they are now solidly for Obama, 23 percent said they support Obama but are open to changing their minds to voting for Sen. John McCain , R‑Ariz., on Nov. 4. Should Obama fail to get those Clintonites to stick with him — especially working-class, white voters in a handful of swing states — his candidacy could be at serious risk.

Nichols said he is still bitter over what he sees as Obama’s disrespectful treatment of Sen. Clinton, D-N.Y., who engaged Obama in a toe-to-toe primary fight that didn’t end until the last primaries and caucuses in June. “She was really treated unfairly. She should have at least been vetted for the vice presidency. That really frustrates me,’’ he said.

But a number of other Clinton backers say they are prepared to accommodate themselves to Obama’s victory.

Another California delegate, Annette Rodrigues of San Jose, said she plans to vote for Clinton. “That’s what I was sent here to do. But I have mixed feelings,’’ said Rodrigues, who plans to vote for Obama in November. A Clinton whip in the Oregon delegation, Sara Gelser, said, “Regardless of what Sen. Clinton says on Wednesday, I am bound by statute to vote for the person I’m pledged for, and I decided to vote for Hillary on Wednesday and on Thursday will join with the Obama campaign.”

Clinton and Obama representatives huddled Monday to discuss Wednesday’s nominating process. Some reports said they were discussing a plan to start the state-by-state roll call vote, stop it partway through — possibly after Clinton’s New York supporters vote — and then hold a convention vote to make Obama’s nomination unanimous.

Such a solution would suit some Clinton delegates. Louisiana superdelegate Patsy Arceneaux, who switched her allegiance from Clinton to help put Obama over the top in June, said, “I hope things are going to go smoothly. I think many people feel this week is going to bring some closure.”