By Geoffrey Garrett
Rick Santorum's wholly unexpected trifecta of primary wins this week in Colorado, Minnesota and Missouri was dwarfed by the damage they did to Mitt Romney, the cashed-up organisation rich Republican nominee-in-waiting the party just cannot commit to.
Santorum's chances of winning the nomination, let alone the White House, remain vanishingly slim, but his victories only underscore the glaring weaknesses and upcoming challenges facing Romney.
Romney's weaknesses are a devastating one-two punch from the Right and the Left.
From the Right, Santorum's main message these days is that the Obamacare health reforms Republicans hate with a rare passion are a carbon copy of the reforms Romney enacted as governor of Massachusetts.
Romney says he will repeal Obamacare, but he is the author of Romneycare. Talk about a policy flip-flop, the label that torpedoed him in 2008, on the biggest domestic policy issue of this year. Worse, longstanding Republican worries that Romney is not a real conservative only intensify the more the Obamneycare charge sticks.
From the Right, the only play left in Newt Gingrich's apparent death spiral is his demonisation of Romney as a standard-bearer for the reckless and heartless Wall Street elite that caused the global financial crisis and walked away from the carnage scot-free.
This economic populism plays well with the Republican's Tea Party wing, but it also shines a very bright light on Romney's Achilles heel against Barack Obama in a general election that the President's State of the Union speech last month showed he will frame in terms of "fairness" for average Americans.
Romney piled up more than $US250 million in assets in his days as founding chief executive of private equity giant Bain Capital. He now pays only 15 per cent tax on his investment income of more than $US20m a year, without having to do a day's work for it.
And Romney's slip-ups are just more grist for the anti-Wall Street mill — a $US10,000 dollar bet during a debate as if it was pocket change and recently saying he doesn't care about the poor — gives Obama the perfect foil for a fairness-based re-election campaign. So why has the Republican establishment come in so solidly behind him?
The answer is that they think they have no choice, after being spurned by other potentially much more attractive candidates, such as former Florida governor Jeb Bush or governors Chris Christie from New Jersey and Mitch Daniels from Indiana.
Despite their financial and organisational muscle, the party's new rules this year mean that Romney will not be able to lock up the nomination much before the party convention in late August in Tampa, Florida.
As of today, Romney can count on only 87 of the more than 1100 delegates he needs to secure the nomination.
More importantly, the primaries until April will use various forms of proportional representation to allocated delegates. US politics is typically winner-takes-all; the Republican nomination process in 2012 is no longer so.
"Accumulate delegates" is the rallying cry for all of Romney's remaining opponents, Ron Paul as well as Gingrich and Santorum. The chances of a "brokered convention" in which no one comes to Tampa with a majority of delegates are still small, but they aren't zero. And many Republicans would secretly relish the opportunity of asking Bush, Christie or Daniels to rescue the party.
Even if Romney navigates the path to the nomination, he would then have to face his Obama woes. In addition to the fairness framing, Obama's secret weapon is the gradually improving US economy. The crucial statistic, the unemployment rate, peaked at 10 per cent in October 2009. It was still 9.8 per cent in November 2010. Today it is 8.3 per cent, and Obama no doubt hopes it may beat 8 per cent by November.
Ronald Reagan was re-elected in a 1984 near sweep of the 50 states despite an unemployment rate of 7.2 per cent, because it had dropped from 10.8 per cent two years earlier. Obama's unemployment reduction will probably be not much more than half as large as Reagan's, but Obama doesn't need a Reagan landslide to win.
For much of the past two years, the story of the Republican bid to unseat a president they loathe was "anyone but Romney". Now the party's elite is stuck with him. But their ambivalence will only grow the more Romney's primary campaign flounders.
The longer the Republic nomination battle goes on, the better for Obama. If in the end Romney can't seal the deal, Republicans can still fantasise about a white knight riding to their rescue on the convention floor: Jeb Bush?
Geoffrey Garrett is chief executive of the US Studies Centre at the University of Sydney