Easy to understand: What happened with Florida and Michigan

Wikipedia: Nullified primaries

In August 2006, the Democratic National Committee adopted a proposal by its Rules and Bylaws Committee stating that only the four states of Iowa (caucus #1), New Hampshire (primary #1), Nevada (caucus #2), and South Carolina (primary #2) would be permitted to hold primaries or caucuses before February 5, 2008.[38]

In May 2007, the Florida Legislature passed a bill that moved the date of the state’s primary to January 29, 2008, setting up a confrontation with the DNC.[39] In response, the DNC ruled that Florida’s 185 pledged delegates and 26 superdelegates would not be seated at the Democratic National Convention, or, if seated, would not be able to vote.[40]

In October 2007, Democrats from Florida’s congressional delegation filed a federal lawsuit against the DNC to force a recognition of its delegates, but the suit was unsuccessful.[41][38] The presidential candidates promised not to campaign in Florida.

Meanwhile, Michigan moved its primary to January 15, 2008, also in violation of party rules.

In October 2007, Obama, Richardson, Biden, and Edwards withdrew their names from the Michigan primary ballot, under pressure from the DNC and voters in Iowa and New Hampshire.[42] Kucinich unsuccessfully sought to remove his name from the ballot,[43] whereas Clinton and Dodd opted to remain on the ballot.[44]

In December 2007, the DNC ruled that Michigan’s 128 pledged delegates and 29 superdelegates would not count in the nominating contest unless it were held on a later date.[45] The Michigan Democratic party responded with a press release noting that the primary would proceed with Clinton, Dodd, Gravel, and Kucinich on the ballot. Supporters of Biden, Edwards, Richardson, and Obama were urged to vote “uncommitted” instead of writing in their candidates’ names because write-in votes for those candidates would not be counted.[46]

None of the top candidates campaigned in Florida or Michigan. The events were described in the media as “beauty contests,"[51] and voter turnout in both states was relatively low when compared with record-high turnout in other states.[52] Nevertheless, Clinton claimed wins in Florida and Michigan, and she flew to Fort Lauderdale on the night of the Florida election to thank supporters for what she called a “tremendous victory."[53]

If the Florida results were to stand, Clinton would receive a net delegate gain of 38 pledged delegates.

If the Michigan results were to stand and the “uncommitted” delegates awarded to Obama, Clinton would receive a net delegate gain of 18 pledged delegates.

As the primaries continued, various groups tried to negotiate a resolution to the standoff between the DNC and the state parties.

The Clinton campaign advocated first for the results to stand and then for a new round of voting to take place in Michigan and Florida, while the Obama campaign deferred the matter to the DNC, while expressing a wish that the delegations be seated in some form.[54]

On all sides, Democrats worried that a failure to resolve the problem could lead to a rules or credential fight at the convention and low Democratic turnout in the general election in November.[51]