UPDATE | May 5, 11am ET : Hillary Clinton's campaign today acknowledged plans to try to win seating of the disputed Michigan and Florida delegations to the Democratic Nation Convention at a meeting of the party's Rules and Bylaws Committee on May 31.

In a statement issued in response to a story on The Huffington Post ("Clinton Camp Considering Nuclear Option," see below), the campaign declared:

"There is no secret plan.... The Clinton campaign has been vocal in stating that the votes of 2.5 million people must be respected. Hardly a day goes by when a Clinton official doesn't publicly declare that the votes of Michigan and Florida count and that the delegations from those states should be seated."

The campaign's public assertions stand in contrast to its response to inquiries prior to publication of the story. At that point, Clinton aides insisted on keeping all comments either off the record or on deep background, or did not respond to questions at all. The campaign statement appeared to be designed to try to reduce the significance of the story.

In a more typical reaction to the story, political analyst Larry Sabato of the University of Virginia said: "Wow. The nuclear option will yield nuclear winter for the Democratic Party."

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Hillary Clinton's campaign has a secret weapon to build its delegate count, but her top strategists say privately that any attempt to deploy it would require a sharp (and by no means inevitable) shift in the political climate within Democratic circles by the end of this month.

With at least 50 percent of the Democratic Party's 30-member Rules and Bylaws Committee committed to Clinton, her backers could -- when the committee meets at the end of this month -- try to ram through a decision to seat the disputed 210-member Florida and 156-member Michigan delegations. Such a decision would give Clinton an estimated 55 or more delegates than Obama, according to Clinton campaign operatives. The Obama campaign has declined to give an estimate.

Using the Rules and Bylaws Committee to force the seating of two pro-Hillary delegations would provoke a massive outcry from Obama forces. Such a strategy would, additionally, face at least two other major hurdles, and could only be attempted, according to sources in the Clinton camp, under specific circumstances:

First, this coming Tuesday, Clinton would have to win Indiana and lose North Carolina by a very small margin - or better yet, win the Tar Heel state. She would also have to demonstrate continued strength in the contests before May 31.

Second, and equally important, her argument that she is a better general election candidate than Obama -- that he has major weaknesses which have only been recently revealed -- would have to rapidly gain traction, not only within the media, where she has experienced some success, but within the broad activist ranks of the Democratic Party.

Under that optimistic scenario, some Clinton operatives believe she could overcome several massive stumbling blocks:

-- Clinton loyalists on the Rules Committee would have to be persuaded to put their political futures on the line by defying major party constituencies, especially black leaders backing Barack Obama. Committee members are unlikely to take such a step unless they are convinced that Clinton has a strong chance of winning the nomination.

Former DNC and South Carolina Democratic Party chair Donald Fowler -- a Hillary loyalist -- would, for example, face an outpouring of anger from South Carolina Democrats if he were to go along with such a strategy.

-- A controversial decision to seat the two delegations, as currently constituted, would be appealed by the Obama campaign to the Democratic National Convention's Credentials Committee.

The full make-up of the Credentials Committee will not be determined until all the primaries are completed, but the pattern of Clinton and Obama victories so far clearly suggests that Obama delegates on that committee will outnumber Clinton delegates. Obama will not, however, have a majority, according to most estimates, and the balance of power will be held by delegates appointed by DNC chair Howard Dean.

For the scenario to work, then, Dean would have to be convinced of Clinton's superior viability in the general election, and that she has a strong chance of defeating McCain next November.

One of the arguments the Clinton campaign is privately making to autonomous "super" or "automatic" delegates, as well as to delegates technically "pledged" to Obama as a result of primary and caucus results, is that the campaign shifted dramatically in roughly mid-February. At that point, Clinton supporters contend, the economy replaced Iraq as the dominant issue among primary voters, and that transition led to Clinton's successes in Ohio, Texas and Pennsylvania.

Clinton people also make the case that the past six weeks have seen examples of Obama's political vulnerabilities: his wife's "proud to be an American" remarks, the emergence of the Rev. Jeremiah Wright controversy, wider coverage of Obama's ties to 1960s radicals Bill Ayers and Bernadine Dohrn, "bittergate," the flag pin imbroglio, and "hand on the heart" accusations -- all impugning Obama's patriotism.

On December 1, 2007, well before the contests were held, the Rules and Bylaws Committee voted to refuse to seat either state's delegation at the August 2008 convention in Denver.

When the contests were actually held, none of the candidates actively campaigned in either state. In Michigan, Obama had his name taken off the ballot. Clinton "won" both contests.

The Obama campaign contends that the primaries in the two states were not legitimate, especially in Michigan where voters could not cast a ballot for Obama. Clinton "won" the Michigan contest with 55 percent, while 40 percent voted "uncommitted" and the remainder went to minor candidates.

Obama manager David Plouffe has argued that the only way to seat the Michigan delegation would be to divide the delegates evenly between Clinton and Obama: "A 50-50 split would be fair."

Many Democrats, including DNC chair Howard Dean, believe it is critically important to reach some kind of compromise to seat the Michigan and Florida delegations in order not to alienate voters in the two battleground states, each of which could be pivotal in the November general election.

In the case of Florida, there are a number of proposals under consideration. One would be to seat the delegation as is, but give each delegate only one half a vote. Another would be to cut the number of Florida delegates in half.

Spokesmen for the Obama campaign declined to discuss their strategies for dealing with the May 31 Rules and Bylaws Committee meeting, or to speculate on what they think the Clinton forces with try to do.