Democrats and Republicans each have had their week in the sun at their conventions, and either Barack Obama or John McCain will win the White House in November. But as in past elections, third party candidates may have a part to play in the electoral drama.

Former consumer advocate and reformer Ralph Nader, who has been on the ballot in most states in 1996, 2000 and 2004, will again put himself before voters this year. He has achieved ballot status in 38 states, and aims to be on seven more state ballots by Sept. 20. Mention his name to Democrats, and you’ll likely hear grumbling and see eyes roll.

Meanwhile, some Republicans, who never warmed to centrist nominee John McCain, are clinging to the failed bid by Texas Rep. Ron Paul to be the party’s standard bearer. At the GOP convention, Paul signs were visible, interspersed in the crowd, and outside the hall, a rally of his supporters drew 12,000.

The Green Party, which nominated Mr. Nader in 2000, has a fresh candidate this time in former Georgia Rep. Cynthia McKinney. Ms. McKinney is on the ballot of 30 states, and the party is fighting for access in several more states.

Another former Georgia representative to Congress, Bob Barr, is a candidate who may have the greatest potential to be a spoiler. Rep. Barr, the Libertarian Party’s presidential nominee, is aiming to be on 45 state ballots. Last week, he filed suit against the Maine Secretary of State’s office, claiming he was denied due process.

Republicans complain that independent presidential candidate Ross Perot cost George H.W. Bush re-election in 1992, siphoning away votes from the incumbent and allowing Bill Clinton to win with less than 50 percent of the vote. Democrats complain Mr. Nader cost Al Gore Florida, allowing George W. Bush to win with 500,000 fewer voters nationwide than Mr. Gore.

Such sour grapes should be set aside, because it’s hard to see third party candidates as anything but good for the democratic process. Mr. Perot effectively introduced the federal deficit as a campaign issue, and Mr. Nader nudged the Democratic Party back to its core values.

One reform to the U.S. presidential election process that has been suggested is approval voting. One version would allow voters to check off as many names as they like on the ballot, and the top two candidates would then be candidates in a runoff. The process liberates voters from the perception of “throwing away” their votes for a minor candidate.

Another reform is to make ballot access for candidates easier. Unlike citizen vetoes and referendums, another name on the ballot does not become a stick in the spoke of the governing.

Come the morning of Nov. 5, the names Barr, Nader, McKinney or Paul may be uttered like swear words by Democrats or Republicans. If so, the fault will lie with the major candidates, not the true outsiders.