After falling further behind in the delegate count Tuesday night, Sen. Hillary Rodham Clinton (D-N.Y.) intensified her push Wednesday morning to seat delegates from Michigan and Florida.

The Clinton campaign has decided that there are two options it would accept: “Either honor the results or hold new primary elections.”

The Obama campaign, however, indicated it remains opposed to a re-vote.

The parrying by the two campaigns came as key Democratic officials in Washington and Florida, including Democratic National Committee (DNC) Chairman Howard Dean and Sen. Bill Nelson (Fla.), signaled they are open to a mail-in re-vote.

Delegates from the two states could turn the closely fought contest between Obama and Clinton. All of the Democratic candidates agreed not to campaign in the two states, and the DNC stripped Florida and Michigan of their delegates for violating rules on when states could hold primaries. Clinton’s name, however, remained on ballots in both states, and she won their contests handily.

Nelson’s endorsement of a re-vote would have significant weight because he last year joined Rep. Alcee Hastings (D-Fla.) in unsuccessfully suing the DNC to seat the state’s delegates.

“In my view, at this late hour, mail-in balloting would be the most practical and fair way to let Florida voters have a full say in the selection of their Democratic nominee,” Nelson said, according to an e-mail sent by his office.

Nelson said his “his first choice” is to seat the delegates based on the Jan. 29 results, and his second choice is to hold a full-scale re-vote, which he has been told is too costly.

“If anyone has another way of accomplishing this, or of honoring the earlier results without splitting the convention, it needs to be put on the table — and now, before it’s too late,” he said.

Florida’s congressional Democratic caucus, however, is on record as opposing a re-vote. It released a statement earlier this week announcing its opposition.

At a speech Wednesday morning at the Hispanic Chamber of Commerce in Washington, Clinton said that Michigan and Florida primary voters “are in danger of being excluded from our democratic process and I think that’s wrong.”

Repeating her assertion that the votes should either be counted or new elections should be held, Clinton said: “I don’t see any other solutions that are fair and honor the commitment that 2 and a half million voters made in the Democratic primaries in those two states.”

In the letter to Plouffe, Clinton campaign manager Maggie Williams said the campaign is “in active consultation with all of our supporters in Florida, including members of Congress.”

“In Michigan, we are in active consultation with the committee appointed by Gov. [Jennifer] Granholm,” Williams wrote.

The Obama campaign said Wednesday that it is open to several options.

Sen. Claire McCaskill (D-Mo.) said on an Obama-arranged conference call with reporters that she and the Illinois senator agree that “it’s very important that we find a way to hear from Florida.”

But Obama said Wednesday that any kind of re-vote is “problematic,” according to The New York Times.

“We were told that Michigan and Florida wouldn’t count, and so we said we wouldn’t campaign there,” Obama said. “Sen. Clinton said the same thing, that they wouldn’t count. Now her campaign is suggesting that they should.”

In a memo Wednesday morning, the Obama campaign wrote that the Illinois senator’s wins in Mississippi Tuesday night and Wyoming last Saturday have effectively erased whatever delegates Clinton won back with her victories in Texas and Ohio last week.

The Obama campaign said Clinton continues to face a nearly impossible mathematical challenge and is grasping at straws in her search for delegates.

“Throughout this entire process, they have cherry-picked states, diminished caucuses, and moved the goalposts to create a shifting, twisted rationale for why they should win the nomination despite winning fewer primaries, fewer states, fewer delegates and fewer votes,” Plouffe wrote in the memo.