Political candidates are not unlike automotive tires: There are retreads, non-treads and worn treads. The key criteria are extended use and whether the candidate still has traction.

Here are unwritten political rules regarding repeat candidacies:

First, a candidate was expected to lose and who narrowly loses, but who performed better than expected, gets a second chance. He or she is a viable retread.

Second, a candidate was expected to win but who loses is a non-tread. The rubber is off the tire. There is no second chance. He or she is no longer credible.

Third, a candidate who loses respectably but then runs for a different office of lesser magnitude is a worn tread. They get another chance.

Here's a look at some shopworn 2010 candidates, and whose tread is still getting traction:

Governor (Republican): Jim Ryan's residual claim to fame is that he lost the 2002 Illinois gubernatorial election to Rod Blagojevich. From a historical perspective, being thrashed by Illinois' first impeached governor is about as humiliating as the Chicago Bears losing the Super Bowl to the Dallas Cowboys cheerleaders.

To be sure, a lot of Illinoisans regret not voting for Ryan instead of Blagojevich, much as they regret not voting for Democrat Glenn Poshard in 1998 instead of George Ryan. The question is: Will they expiate their guilt and seek atonement by voting for Ryan in 2010? Don't count on it.

After 8 years as state attorney general, and after successfully battling cancer, the well known and well respected Ryan should have won the governorship in 2002. But the sins of George Ryan were gurgling to the surface, and the slick, superficial and wholly amoral Blagojevich ran as the candidate of "change." Blagojevich blasted Ryan for not investigating the governor, for being part of the corrupt Springfield culture, and for opposing abortion rights.

Ryan's stiff, uninspiring demeanor and vacuous campaign message was no match for Blagojevich's energy, deal-making and demagoguery. After 26 years of Republican rule, voters wanted a Democratic governor. Blagojevich promised state jobs to precinct captains, spent $25 million, and prevailed by a solid 252,080-vote margin, getting 52.2 percent of the vote; he won 35 of Illinois' 102 counties and carried Cook County by 468,974 votes.

Ryan won the Collar Counties by a weak 147,338-vote margin and Downstate by just 69,556 votes. To win statewide, a Republican needs to win the Collar Counties by 250,000 votes and Downstate by 300,000 votes.

After 8 years in the political wilderness, a forgotten and forlorn figure who elicits neither sympathy nor voter regret, Ryan is again seeking the governorship. How to characterize him? He's more of a retread than a non-tread. He was the initial frontrunner in 2002, but, given the George Ryan scandals, his defeat was foreordained. Now, incredibly, he is the frontrunner for the Republicans' 2010 nomination.

According to his rivals' internal polling, Ryan is leading the field, amassing a consistent 25 percent support against six contenders. Republican voters know him and not the other candidates, and "simple familiarity" may be enough to get him nominated, one strategist said.

According to Republican insiders, Ryan's nomination would ensure the election of a Democrat as governor. "We need to focus on the future, not the past," said another Republican official. "He is the past. He'd be a disaster."

The "ABR" (Anybody But Ryan) Republican primary field includes state Senators Kirk Dillard and Bill Brady, DuPage County Board Chairman Bob Schillerstrom, businessmen Andy McKenna and Andy Andrzejewski, and publicist Dan Proft. McKenna will spend at least $5 million on ads, Dillard has former governor Jim Edgar's endorsement, and Brady is relying on his Downstate base and ripping "Chicago-style corruption" in Springfield.

With the Feb. 2 primary less than 2 months away, none of the ABRs has broken out of the pack. Most have been castigating Blagojevich-induced "pay to play" corruption and Governor Pat Quinn's incompetence while promising not to raise taxes -- and getting no traction. All are social conservatives, and all support the death penalty.

So what to do? Either find a defining issue or begin blasting away at Ryan. As for the former, term-limiting could be helpful. A candidate could pledge to serve only one term, focus all effort on solving the state's budget crisis, and forgo campaigning and fund-raising. "A 24/7 governor, not a politician" -- that's the theme.

If successful, the governor could run for U.S. senator in 2014 against Democrat Dick Durbin; if unsuccessful, the governor wouldn't get reelected anyway.

As for the latter, Ryan has mountains of baggage. During his 2002 campaign he received $500,000 in contributions from Stuart Levine, his finance chairman, who was convicted in 2006 of federal fraud and money-laundering charges. Levine was part of Blagojevich's "pay to play" scheme, and he got pension investment deals for Ryan contributors. Ryan professes ignorance of Levine's machinations, noting only that they were law school classmates and friends. In addition, Ryan supports the moratorium on Illinois' death penalty which was imposed by George Ryan.

And then there's the Jeanine Nicarico case. As state's attorney, Ryan prosecuted and then re-prosecuted Rolando Cruz for the girl's murder, and got the death penalty for Cruz. But the "DuPage 7" trials implicated four sheriff's officers and three prosecutors in plotting to falsely convict Cruz. Brian Dugan recently pleaded guilty to the crime, Cruz has been released, and Ryan apologized.

The bottom line: Republicans desperately want to avoid revisiting Levine, Cruz and George Ryan's moratorium. But if they don't, Ryan could be nominated. For every contender, it's a lose-lose situation. Taking a shot at Ryan will run up his negatives, and also the attacker's.

My prediction: Ryan's DuPage County base is diluted by three other DuPage contenders: Schillerstrom, Dillard and Andrzejewski, and the "liberal" vote in a Republican primary barely exceeds 10 percent. In 2006 wealthy businessman Ron Gidwitz, a social liberal, spent more than $7 million, emphasized fiscal issues, and got 80,068 votes, which was 10.1 percent of the total cast.

Ryan's support is squishy soft, dependent solely on residual name identification, and it won't exceed 25 percent. But that's more than anybody else at the moment. Unless Dillard, Brady or McKenna breaks out of the pack very soon, Ryan will be nominated.

Treasurer (Republican): Dan Rutherford, a Pontiac state senator, paid his dues by running for secretary of state in 2006. He wasn't expected to win, was squashed by Democrat Jesse White, and got only 33.1 percent of the vote. Rutherford is a worn tread, not a retread. He's running for treasurer in 2010, has cleared out the Republican primary, and looms as the favorite to win the post.

Comptroller (Republican): Like Jim Ryan, Judy Baar Topinka was buried by Blagojevich's hypocritical rhetoric and sleazy fund-raising. Illinois' treasurer for 12 years, Topinka endured a rough and financially draining 2006 Republican primary for governor, winning with 38.2 percent of the vote, and then was subjected to a summer-long television advertising onslaught which destroyed her credibility. In the election, Topinka amassed 1,369,315 votes (39.3 percent of the total). That was 225,645 votes fewer than Ryan's total in 2002.

Topinka surely is a no-tread for governor, but she has shifted to a bid for comptroller in 2010. In the primary, she faces Jim Dodge and Bill Kelly. The Democrats are David Miller and Raj Krishnamoorthi. Being both well known and well worn, Topinka will be returned to public office.

Maine Township (Park Ridge, Des Plaines, Mount Prospect): In this northwest suburban area, it would be inaccurate to compare politicians to tires. Some could be wheels, rims, wheel wells or even lug nuts. Mark Thompson, the township's embattled Republican committeeman, has sought local office 10 times since 1981, winning five times as a township official and twice as committeeman, but he has lost twice for township supervisor and in 2009 for Des Plaines mayor.

State Representative Rosemary Mulligan (R-65), an erstwhile Thompson ally, has filed to run for Republican committeeman in 2010, and she will trounce Thompson, but Thompson also is running for county commissioner in the 17th District, which stretches from Maine Township south to Orland Park. The incumbent is Liz Gorman, who is a bitter enemy of fellow Republican commissioner Tony Peraica (R-16). Peraica is backing Thompson, as are the Wheeling Township Republicans. A Thompson upset is possible.

40th House District: This column recently detailed "Dumb Deb" Mell's escapades before the Chicago Board of Elections. Deb Mell is the daughter of Alderman Dick Mell (33rd), and "Big Daddy" made her a state representative in 2008. She moved in 2009 but neglected to re-register to vote. Not to worry.

When Joe Laiacona, her 2010 Democratic foe, objected to her petitions, "Big Daddy's" election lawyers argued that the Illinois Constitution supercedes state law, meaning that qualifications for holding the office (being a resident for 2 years) trump requirements for ballot access (being a registered voter and a resident). "Dumb Deb" will be going back to Springfield, proving that candidates with the right DNA don't need any tires.