Mr George Bush scored an important and strategic victory by defeating Mr John McCain in the South Carolina Republican primary, which will give him real momentum today in Michigan. But it was achieved at a decided political price - the emphatic assertion by Mr Bush of his right-wing credentials against the reformist policies proclaimed by his opponent. It remains to be seen whether this is a tactical matter or represents an underlying shift of policy which will determine the overall campaign.
Mr Bush and his team were shocked by Mr McCain's stunning victory in the New Hampshire primary earlier this month, as was the entire Republican Party establishment. In the purely competitive sense, Mr Bush's decision to reinvent his campaign in South Carolina by moving sharply to the right and making extensive use of negative advertising has paid off handsomely. It establishes his credentials as a ruthless campaigner capable of learning the lessons of failure. Unless he had pulled it off, he risked the entire commitment he has made so far. In the event, the contest sharpened his campaigning technique and allowed him to exploit several mistakes by the McCain camp, including an assertion that Mr Bush is less trustworthy that President Clinton.
Mr McCain's appeal to the more liberal strain of Republican supporters has struck home throughout the United States, lending credibility and interest to the early primaries' function as a bellweather of opinion and a wake-up call for the presidential election year. His support for campaign finance reform, his opposition to mindless tax reductions that undermine pension and welfare schemes and his comparatively tolerant position on abortion have corrected popular stereotypes of Republicanism, especially among the US media. He is deliberately aiming to attract independents and dissident Democrats, rather like Ronald Reagan did in the early 1980s.
In the South Carolina campaign, Mr Bush turned the tables on Mr McCain's liberal conservatism by portraying it as set by a Washington insider agenda and eccentrically at odds with popular opinion in this southern state. Mr Bush's speech at Bob Jones University - which is opposed to Catholicism and bans inter-racial marriage - sent messages out that will haunt him through his subsequent campaigning. His alliance with the anti-abortion Christian conservatives is likewise defining. So is his unqualified reassertion of the merits of the death penalty. Taxation is to be kept as low as possible.
This is not the compassionate conservatism Mr Bush made his own when campaigning against the fundamentalist right-wing of the Republican Party in the early stages of this campaign. If he successfully sees off Mr McCain's challenge, he will have to decide how to play the political game against the Democrats. There are many independents and floating voters who have supported Mr McCain and would not take to the programmatic platform Mr Bush used to defeat him in South Carolina. In such a huge and diverse society as the United States, they will have their voice. Some of that effect could be apparent in Michigan today.