Both figurative and literally, registered Democrats are leaving requested mail ballots on the table. Democrats are returning the mail ballots at a lower rate than Republicans, leading to wide disparities among the ballots that have been cast compared to the ballots that are still sitting on kitchen tables across the country.
Many states require mail ballots cast by domestic civilians to be returned to election officials by election day, although some -- notably Ohio -- allow mail ballots to be postmarked by the day before the election and will continue to accept them until Nov. 16.
Persons who requested a mail ballot but attempt to vote in-person on Election Day should bring their mail ballot with them to the polling place, if they still have it. If they do not, most states require these individuals to cast a provisional ballot to ensure that they do not vote twice, once by mail and once in-person. (This is the easiest form of vote fraud for election officials to detect, so don't even think of trying it.)
Here are some numbers that will give the Obama campaign heartburn in the key states of Iowa and Florida.
In Florida, 406,634 registered Democrats have not returned their mail ballots compared to 362,920 Republicans. In comparison, registered Democrats have returned 700,970 mail ballots compared to 781,043 Republicans. Thus, even though Republicans outnumber Democrats in returned mail ballots by a wide margin, more Democrats have yet to return their ballot.
In Iowa, 40,601 registered Democrats have not returned their mail ballots compared to 21,224 Republicans. Iowa is not reporting their ballot status in the same way as Florida, but we know that among all ballots cast -- both by mail and in-person -- registered Democrats outnumber Republicans 261,166 to 198,130. And while that may look like a comfortable margin, keep in mind that Iowa Republicans have historically voted in-person on Election Day in large numbers; John Kerry won the Iowa early vote in 2004, but lost the state.
It is not out of the question that a person with a mail ballot sitting on the counter may think of themselves as a voter even if they have not filled out the ballot. If so, when surveyed they may respond in the affirmative that they have voted even if they have not. The polling within these states may thus favor Romney slightly more than we may think.
More early vote statistics can be found here.
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