RALEIGH, N.C. — Sitting on the sunny patio of a Raleigh coffee shop last weekend, Averell "Ace" Smith hardly seemed the kind of guy to strike fear into a politician's heart.

The 49-year-old California political operative — who helped Hillary Rodham Clinton to victories in the California and Texas Democratic presidential primaries and is running her North Carolina operation — was a study in bland: beige polo shirt, beige khakis, bright blue eyes framed by wire rim glasses, a fringe of gray hair around a pink scalp.

Yet in interviews, people — many of them fellow Democrats — frequently use melodramatic imagery to describe him.

"I believe that every life lesson in politics can be extrapolated from 'The Godfather,'" said Chris Lehane, a Democratic strategist and friend of Smith's who has worked for the Clintons. "Some people are Fredos; at game time they disappear. There are Sonnys who yell and scream. ... The most effective ones are the Michael Corleones — very quiet, they know under which rib to insert the knife. ... Ace is a Michael Corleone."

The next round of the seemingly endless quest for the Democratic nomination takes place Tuesday, when Indiana and North Carolina vote. They are the first contests since April 22, when Clinton beat Barack Obama in Pennsylvania.

The race is close in Indiana, and Obama's once double-digit lead in North Carolina, which has a sizable black electorate, has shrunk to a single digit in most polls. The fact that the Clinton campaign stationed Smith here signals how crucial the state is to her, and that she intends to fight for every vote.

"Everyone knew that Pennsylvania was essentially going to be a walk for Clinton, and that the whole thing would come down to Indiana and North Carolina," said Joe Trippi, a top adviser to former presidential candidate John Edwards. "Guess where Ace Smith is? I don't think that's an accident."

If Smith can help Clinton seriously narrow Obama's margin of victory, or even beat him in the Tar Heel State, the New York senator's claim that she is the more electable of the two will gain considerable strength.

A victory also would burnish Smith's reputation as a top-notch strategist, and perhaps change his image as a fearsome practitioner of a dark political art: opposition research.

Ben Austin, a Democratic political consultant who worked in the Clinton White House and now supports Obama, put it this way: "He is one of the few balding, bespectacled guys who I wouldn't want to run into in a dark alley."

But not all Democrats are fans.

"It's admirable if you can lie and get away with it," said Kam Kuwata, a consultant to former Los Angeles Mayor James Hahn, who ran against Smith's client, Antonio Villaraigosa twice — successfully in 2001, unsuccessfully in 2005.

Attorney Ken Khachigian, a longtime Republican strategist, is a reluctant admirer. He faced off with Smith in 2006 when his client, former California state Sen. Chuck Poochigian, lost against Jerry Brown for California attorney general. "He does what he has to do," said Khachigian. "He'll be relentless and tough. He fits right in with the Clinton war machine."

Khachigian figured in Smith's biggest political heartbreak. In 1990, Smith was deeply involved in the campaign of his father, longtime San Francisco district attorney Arlo Smith, who ran against Dan Lungren for state attorney general. Smith won on election day, but lost two weeks later when absentee ballots barely put Lungren over the top.

Even now, Smith has a hard time talking about that.

"I'll tell you something," Smith says. "I have a tremendous amount of empathy for President Clinton. ... I mean, if you see someone criticizing, attacking your father, in my case, or his wife, in his case, you just want to slug 'em."

Nevertheless, he said, "You cannot run campaigns if you can't remain calm in the face of adversity and bad polls. The best thing is to be as dispassionate as possible."

Up and down the state of California, political reporters have Ace Smith stories. They speak of boxes landing on their desks, ammunition culled from public records that Smith hopes will shape the campaign narrative.

The topic might be voting records, inflated resume claims, long-ago brushes with the law or questionable business dealings. Not infrequently, stories ensue. Reporters say he is charming, helpful, tenacious and not averse to going over their heads to editors in an attempt to shape or kill a story if he senses it is going to make a client look bad.

While he specializes in California races, Smith has worked all over the country. In the late '80s, he traveled the country as political director of the Democratic Congressional Campaign Committee. In 1992, in advance of Bill Clinton's first presidential campaign, he produced "vulnerability studies" (the genteel term for "oppo" on your own guy) for the Arkansas governor.

When Smith heard that the Clintons wanted him in North Carolina, he did what he always does before parachuting into a new state: He grabbed his copy of "Inside U.S.A.," a 1947 guidebook by the journalist John Gunther.

"I always start there," he said. Then he picks up a guidebook from AAA. "I read that start to finish 'cause it has all these odd little facts and pieces about small towns and you get a real flavor for what's going on."

This year in particular, small towns are a major part of his strategy. With Obama faring better in the big cities and among the affluent and well-educated, hitting the smaller population centers has been critical to Clinton's success.

"(Smith) is enormously talented at looking at voting patterns and demographics, and figuring out where you can actually put votes together," Lehane said. "I remember the day before the California primary, there were polls showing it was a dead heat and some even had Obama surging ahead. The campaign was hectoring him from the East Coast and he guaranteed (them) a 10-point win, which is exactly what he delivered."

North Carolina is a different story.

"In California, Hillary went in with an institutional and demographic advantage," said Ben Austin, referring to her name recognition and popularity among Hispanics. "In North Carolina, Obama goes in with the demographic advantage, and if Ace can pull that out, he will truly have proved his mettle."