Both are winless after more than a dozen state contests, holding in single digits in the polls, with no expectation of doing better down the road. But each professes a unique sense of purpose and vows to stay in until the end.
For Kucinich, it's to shine a light on his opposition to the Iraq war and his plan to bring U.S. troops home.
"It is at the convention where I will win the nomination, based on the emergence of Iraq as the defining issue," the Ohio congressman predicted last week.
Sharpton, the only black candidate remaining, wants to help tailor the party platform to reflect minority concerns.
"I'm going to go all the way because we cannot be disrespected or marginalized," he told a Baptist congregation in Richmond, Va., last Sunday.
The eventual nominee — Massachusetts Sen. John Kerry is the current front-runner — will almost certainly challenge President Bush and the Republican Party over the administration's Iraq policy, including the failure to find weapons of mass destruction, and the GOP's record on issues important to blacks, Hispanics and other racial minorities.
Yet while neither Kucinich nor Sharpton has persuaded enough voters that he can beat Bush in November, each argues that his continued presence in a field that has gone from 10 candidates to five, despite calls by establishment Democrats for lagging candidates to drop out, helps keep those issues alive.
"We have a president who is saying he wants to get the facts, and yet he sent people to war without the facts. And we have Democratic front-runners who said they were misled, and yet they sent people to war," Kucinich said. "Where's the accountability?"
Sharpton has had more success in rankling his opponents during televised debates, such as when he criticized Howard Dean for failing to appoint any minorities to his Cabinet when he was Vermont's governor. He also has a knack for getting off some of the funniest debate lines.
In a forum shortly after Dean was criticized for delivering a ranting concession speech after losing Iowa's caucuses, Sharpton said: "I wanted to say to Governor Dean, don't be hard on yourself about hooting and hollering. If I had spent the money you did and got 18 percent, I'd still be in Iowa hooting and hollering."
Kucinich and Sharpton's stump speeches rarely make headlines, and their showings in the primaries and caucuses are often summarized in obligatory sentences at the end of the larger campaign story. Their campaign strategy is hardly routine: While most of the field camped out in New Hampshire ahead of its Jan. 27 primary, Sharpton crisscrossed South Carolina. On Wednesday, with the focus on Wisconsin's upcoming primary, Kucinich toured his home state of Ohio.
Kucinich has placed no better than third in any of the 14 contests to date. But last Sunday in Maine, he registered in double digits for the first time, with 15 percent of the vote in that state's caucuses — a feat his campaign promoted.
"He has done so, amazingly, during a virtual blackout of his campaign by the national media," the Kucinich campaign said in an e-mail. "The strength of the Kucinich campaign has begun to show itself, and will continue to show itself, all the way to the convention."
Sharpton's best finish was third in South Carolina, where he campaigned more than any other rival, trying especially hard to galvanize the black vote. He finished with 10 percent on primary night.
Sharpton has 12 delegates and Kucinich two, compared to 538 for Kerry. It takes 2,162 to win the nomination.