Have no doubt about this: If ailing Cook County Board President John Stroger is on the ballot in November, he will lose to Republican Tony Peraica.

Stroger suffered an incapacitating stroke just prior to the March 21 primary election. Nevertheless, in the Democratic primary, according to unofficial returns, Stroger beat Forrest Claypool by 22,794 votes, with 52.3 percent of the votes cast. Stroger's level of support among white voters was notably soft. Claypool got a hefty 69.8 percent of the county's suburban vote, carrying the suburbs by 57,341 votes. But Stroger got 90 percent of the vote in Chicago's black wards, propelling him to an 80,135-vote win in the city, with 61.2 percent of the votes cast.

Two conclusions can readily be drawn:

First, absent Stroger's stroke, Claypool would have won. A spike in the black vote put Stroger over the top, as black voters suddenly recognized Stroger's racial contributions.

Turnout was abysmally low. In the board president's race it was just 500,536, according to the latest returns. In 1994, when Stroger beat Aurie Pucinski and Maria Pappas in the Democratic primary, turnout was 626,457. Stroger got 295,358 votes (47.1 percent of the total) in that contest, while this year he won 261,665-238,871. His vote was down by nearly 35,000, but the anti-Stroger vote declined by nearly 100,000.

As the primary approached, Claypool's television ad attacks on Stroger as a tax hiker and inept administrator clearly were resonating. Claypool postured as a reformer, and in a political environment suffused with scandals, from the city Hired Truck Program revelations to the George Ryan trial, he was getting traction. Although Mayor Rich Daley endorsed Stroger, two of his key insiders, consultant David Axelrod and U.S. Representative Rahm Emmanuel, endorsed Claypool and actively worked for him. In addition, the Service Employees International Union, a key Daley supporter, pulled its resources from Stroger 2 weeks before the primary.

And the state's two most prominent black Democrats, U.S. Senator Barack Obama and U.S. Representative Jesse Jackson Jr., were neutral in the race, refusing to endorse Stroger. The incumbent was on the brink of defeat.

Second, political observers assumed that Daley, facing a tough 2007 mayoral contest against Jackson and, possibly, U.S. Representative Luis Gutierrez, needed a Stroger win. The county employs more than 25,000 workers, and Stroger, as County Board president and as the South Side 8th Ward Democratic committeeman, controls thousands of jobs, both in his ward and throughout the South and West sides. In 2007 he would be Daley's first line of defense against Jackson. Stroger supported Daley against Harold Washington in 1983 and against Gene Sawyer and Tim Evans in 1989, and he even backed Dan Hynes against Obama in 2004.

But a secondary presumption was that Stroger, wounded by Claypool's negative campaign, would be vulnerable to a Republican opponent in November. If Claypool, who formerly was Daley's chief of staff, were nominated, he would easily beat Peraica, and county government would remain under John Daley's control. A Peraica win would upset everything.

But then Stroger had a stroke on March 14. Claypool raised more than $2 million, much from sources who had previously contributed to Daley. Was he the "stealth" Daley candidate? Claypool concluded his campaign with a whimper, not a bang. How can you attack a sick guy? And when a Sun-Times columnist said that his first reaction was to wonder if Stroger had somehow faked his illness, black voters exploded in outrage.

The key: Back in 1994 Stroger got 82.3 percent of the vote in Chicago's black wards; this year he got more than 90 percent. Back in 1994 Stroger got 26.4 percent in the predominantly white Northwest Side wards; this year he got more than 35 percent. Back in 1994 all the Northwest Side Democratic committeemen backed Stroger, Daley's candidate. This year 39th Ward Committeeman Randy Barnette and 47th Ward Committeeman Gene Schulter backed Claypool, and the remaining committeemen tepidly backed Stroger.

"They didn't do (anything) for Stroger," said Frank Coconate, chairman of the Northwest Side Democratic Organization, referring to the area committeemen. Coconate, fired from his city water management job after endorsing Jackson for mayor, is now employed as an organizer for the SEIU. "The word came down that we should stop working for Stroger," Coconate said. "Clearly, the fix was in. The Daley people were double-crossing Stroger and backing Claypool. But I wouldn't accept that. My Democratic volunteers kept working for Stroger."

But all this might soon be moot. A similar situation exists in Israel. Prime Minister Ariel Sharon had a stroke late last year, and his new Kadima Party, bolstered by a sympathy vote, likely will keep power. Stroger, in illness, was viewed as an icon by blacks. However, voters' sympathy in March will have dissipated by November. Stroger must be seen as active, energized and vocal.

Compassion aside, voters are not about to re-elect a Stroger if they don't think he can perform his duties. For Peraica, a best-case scenario is that Stroger refuses to resign his nomination. In that situation, Peraica will win.

Under state law, a nominee can resign and be replaced by the local, county or state party committee in that jurisdiction. After Jack Ryan resigned his nomination in 2004 when stories of his sex escapades surfaced, the Republican State Central Committee picked his replacement. If Stroger resigns his 2006 nomination more than 30 days before the November election, the county Democratic Party, consisting of the 50 city ward committeemen and the 30 suburban township committeemen, most of whom are Daley loyalists, will pick his replacement.

The political imperatives suggest that a black replacement be picked, with Illinois Secretary of State Jesse White at the top of the list. At age 71 White would be a transitional figure, serving for a term or two, and the state Democratic Party could then name a Downstater to replace him on the ballot for secretary of state, since Downstaters are miffed that every Democratic statewide nominee in 2006 is from Cook County. The selection of Claypool to replace Stroger would enrage blacks, as would the choice of County Commissioner John Daley, the mayor's brother and the County Board Finance Committee chairman, who really runs county government.

Stroger's son, 8th Ward Alderman Todd Stroger, surely would be appointed to his commissioner's nomination, but not to the presidency, because he's not deemed sufficiently seasoned for the job. Another possibility is Dorothy Brown, the clerk of the Circuit Court, a post that controls 2,800 jobs. The Daley forces don't need to placate Brown. Her 2007 path to the mayoralty is already blocked by Jackson.

Outgoing Sheriff Mike Sheahan might be considered; he has been feuding with Stroger for years about jail funding, but he wants to eject himself from county squabbling. A white Daley ally as a replacement for Stroger would surely ignite black rage. The perfect choice could be Commissioner Mike Quigley, a Lakefront liberal/independent and a persistent critic of both Daley and Stroger who announced his 2006 candidacy for board president but then withdrew and endorsed Claypool. He gives Peraica no target, and his liberalism would capture the black vote anyway.

The unfolding Stroger situation will be a soap opera. Todd Stroger and his allies, including state Senator Donne Trotter (D-17) and Alderman Ricardo Munoz (22nd), will be arguing that a black candidate must be chosen. Don't be surprised if John Stroger's recovery becomes the gist of daily news bulletins, most of which are positive and sympathetic.

If Stroger is still a candidate by early autumn, that puts Peraica in the same quandary Claypool was in. How do you attack a sick man?

The bottom line: Historically in Cook County, Republicans only win when they get at least 65 percent of the suburban vote and 33 percent of the Chicago vote. Claypool got 38.8 percent of the city vote. Could that vote move en masse to the Republicans?

The Cook County Republican base vote is about 30 percent, or about 400,000 votes. That means that to win, Peraica needs at least 75 percent of the white vote and almost all of Claypool's 339,725 primary votes.

In 2002 Stroger beat Republican Chris Bullock by 870,059-402,185, with 68.4 percent of the total. In 1998 he beat Pucinski, then a Republican, by 802,360-469,418 (63.1 percent). In 1994 he beat Joe Morris by 681,078-397,241 (62.9 percent).

My early prediction: The 2002 election turnout in Cook County was 1.4 million, and in the board president's race it was 1,272,244. If it's the same in 2006, Peraica needs 650,000 votes to win, and he must shave 225,000 votes off Stroger's 2002 vote. If Stroger stays on the ballot, Peraica will win. But if Stroger departs and is replaced by White or Quigley, Peraica will lose big.