We are seeing hints of this strategy in the analysis of 2012 election results, even before the votes are counted. Today I was a guest on Diane Rehm’s national radio talk show, which has many liberal listeners. Before the end of the first commercial break, the show had received dozens of e-mails asserting that a Mitt Romney victory could only be the result of racism. This narrative didn’t even admit the possibility that voters might be discontented with economic conditions or impressed by Romney’s proposals.

On MSNBC today, former Democratic National Committee Chairman Howard Dean asserted that if Obama loses Ohio, the likely explanation is fraud. “Given the vote and the leading of the polls in Ohio,” he said, “the only way he can lose is if people are prevented from casting their ballots either voting machines that aren’t functioning right or other forms of harassment.” In the event of an Obama win in Ohio, it is easy to imagine similar accusations from the right. A recent PPP poll found that 62 percent of Republicans in Ohio think Democrats will engage in voter fraud to make sure that Barack Obama wins. About 50 percent of Ohio Democrats think the GOP will engage in fraud to ensure a Romney victory.

I don’t want to deny that racism or corruption can play a role in American elections. But this kind of preemptive de-legitimization is dangerous. It gives the impression of partisans laying the groundwork to dispute any electoral outcome they don’t prefer. A margin of the electorate seems to believe – or pretends to believe – that any presidential election they lose must be the result of conspiracy or malevolence.

These charges make it easier for partisans to tend embers of anger and resentment for years after an election is decided. And this is precisely the problem. Every presidential campaign, at some point, must end for the process of healing and governing to begin. When partisans refuse to accept the legitimacy of electoral outcome, they are engaged in a campaign that never ends.

The election or reelection of a president is the way a divided, exhausted democracy recuperates. But conspiratorial questions about a president’s legitimacy are a slowly releasing poison. The health of our democracy will depend, in part, on the judgment and public spirit of the losers – whoever they might be tonight.