Mitt Romney and his wife Ann Romney greet supporters during an Illinois… (Scott Olson / Getty Images )
Reporting from Chicago —
Six times in the last 36 years the Illinois primary has settled a presidential nominating fight. It is too soon to declare this year's turbulent GOP contest over. But the end may be visible from the top of Chicago's John Hancock Tower.
Mitt Romney's commanding win in the Illinois primary stamps him -- once and for all -- as the overwhelming, indisputable and probably uncatchable favorite to lead Republicans into the fall campaign against President Obama.
There are two tracks to the GOP race, now in its third month of balloting, and the former Massachusetts governor is winning both.
The most important is the fight to accumulate the 1,144 convention delegates needed to secure the nomination. Romney has done consistently well in that effort and helped himself greatly Tuesday by winning the overwhelming majority of delegates.
With the results in from more than half the states, Romney has now opened up a sizable lead over the rest of the field and is widening that margin with each contest. The difference is a superior political operation and the financial wherewithal to compete anywhere and everywhere that votes are being cast.
By contrast, his main rival, Rick Santorum, was again forced to cede a significant chunk of Illinois delegates when he failed to qualify for the ballot in four of the state's 18 congressional districts. Slowly but inexorably, that organizational disadvantage is undermining Santorum's slim chances of overtaking Romney and snatching the nomination away.
As for the remaining candidates, former House Speaker Newt Gingrich has now lost 30 of the last 31 contests and looks increasingly like Texas Rep. Ron Paul: a candidate who is running but falling further and further behind.
The second aspect of the race involves perceptions; here Romney has fared less well.
He has repeatedly fallen short when opportunities came to wrap up the contest: in South Carolina, Ohio, the South. That has kept Santorum alive and fostered doubts about Romney's saleability within his own party, much less with the independents and discontented Democrats whose backing he would likely need in order to capture the White House.
Simply put, winning makes a candidate look like a winner. Up to now, Romney has struggled to consistently project that aura. While his victory speech Tuesday night was flat -- the candidate was clearly exhausted -- and he stumbled over several applause lines, the important thing was the headline emerging from Illinois: Romney in a romp.
As a result, the Republican bandwagon may be finally starting up -- fired by the concerns of an increasingly nervous party establishment. To Romney's great benefit, the calendar also looks much friendlier going forward.
Santorum is a favorite to win Saturday in Louisiana, continuing his strong performance in the deeply conservative South.
But Romney is on more agreeable terrain in Maryland, Wisconsin and Washington, D.C., which vote April 3. (Santorum didn't even make the ballot in the nation's capital.)
Then comes a three-week lag until April 24 and contests in five states, including a primary in Santorum's Pennsylvania that ranks as a must-win for the former senator.
Santorum marked his second-place Illinois finish by declaring victory, of a fashion.
"We won the areas that Republicans and conservatives populate," he told supporters Tuesday night in Gettysburg, Pa., taking no small amount of creative license. (There are several Republican lawmakers representing Chicago's "collar counties," which Romney won handily.)
But Santorum needed to do much better than he did to emerge as a serious threat to Romney. If nothing else, he had to broaden his support beyond the core of social conservatives and Christian evangelicals who powered him to victories in the South and low turnout contests in Missouri, Colorado and Minnesota.
Illinois, with its sizable population of moderate Republicans, offered the perfect opportunity, but it went unrealized.
Campaigning over the weekend in rural Illinois, Santorum told a crowd, "If we're able to come out of Illinois with a huge or surprise win ... I guarantee you that we will win the nomination."
He didn't, and that makes it highly unlikely he can.
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Analysis: Illinois primary win boosts Romney's inevitability case