There is nothing like ten straight victories to put a smile on people’s faces: on board the campaign aircraft of Barack Obama yesterday his aides were jubilant, the candidate himself was wearing a big winning grin and even the detail of six Secret Servicemen appeared glad to be along for the ride.

Yet beneath the undeniable sense that this campaign is turning into a juggernaut there is a clear strategy being soberly mapped out by Mr Obama’s aides after his landslide wins in Wisconsin and Hawaii, a plan not just to achieve victory over Hillary Clinton but to send him all the way to the White House.

Underlying this strategy is an effort to counter growing concerns that Mr Obama is at risk of being perceived as “all hat and no cattle”, as Mrs Clinton alleged at a rally in Texas last week, and in frequent similar attacks in recent days. John McCain, in his victory speech on Tuesday night, referred to the “eloquent but empty Obama”.

At a huge rally in Dallas yesterday Mr Obama rebutted Mrs Clinton’s accusations earlier in the day that he lacked substance. “Today Senator Clinton told us there is a choice in this race. I couldn’t agree with her more. Contrary to what she’s been saying, it’s not a choice between speeches and solutions.

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“It’s a choice between the politics that promises more divisions and distractions that didn’t work in South Carolina and didn’t work in Wisconsin and will not work in Texas. Or a new politics of common sense, common purpose, shared sacrifice and shared prosperity.”

In his prime-time victory speech before an overflow crowd of 18,500 in Houston on Tuesday night, Mr Obama mixed his usual soaring message of hope and empowerment with significantly more references to his policy prescriptions — on taxes, healthcare and pensions — while also reminding his audience that he is taking nothing for granted.

“The change we seek is still months and miles away,” he declared to an ecstatic and largely African American crowd. “Because understand this, Houston: as wonderful as this gathering is, as exciting as these enormous crowds and this enormous energy may be . . . it is going to take more than big rallies. It’s going to require more than rousing speeches. It will also require more than policy papers and positions and websites.

“It is going to require something more, because the problem that we face in America today is not the lack of good ideas. It’s that Washington has become a place where good ideas go to die.”

In the short term the goal is to maintain Mr Obama’s momentum by exceeding expectations in the March 4 contests of Ohio and Texas, states that should favour Mrs Clinton because of the former’s heavily blue-collar demographics and the latter’s large Hispanic population. Victory in either could doom the campaign of Mrs Clinton.

Yet Mr Obama’s aides believe Mrs Clinton when she says that she will press on for weeks to come, no matter the outcome on March 4. The aim is to hold, and preferably increase, Mr Obama’s current 150 lead among elected delegates.

It is an intensifying campaign to persuade the Democratic party’s unelected super-delegates — who could decide the contest — not to buck the will of the voters.

“The game now is for the delegates,” David Axelrod, Mr Obama’s chief strategist, told The Times. His campaign manager, David Plouffe, said: “The goal is to maintain and hopefully build our lead in pledged delegates.”

Mr Obama’s aides say that the results from Wisconsin, and in the Potomac primaries of Virginia, Maryland and Washington DC on February 12, prove their contention that he is building a broad coalition of whites, blacks, independents — and now even women and blue-collar workers — that is rapidly eroding Mrs Clinton’s core constituencies.

Of his ten consecutive wins Mr Obama won many in states where he trailed Mrs Clinton badly on New Year’s Day.

Mr Obama is using his string of victories as proof that the American people are rejecting the divisive Clinton and Bush years. “The American people have spoken out and they are saying we need to move in a new direction,” he declared in Houston.

All eyes now turn to the March 4 contests of Texas and Ohio. In Texas Mr Obama is focusing heavily on the state’s African American population, especially in Houston and Dallas, but he also hopes to make inroads into its large Hispanic vote, traditionally supportive of Mrs Clinton.

Mr Axelrod said that the win in Wisconsin is encouraging ahead of Ohio, which has similar demographics. Mr Obama has also been prevailing over Mrs Clinton when he has time to devote to a state. The more he campaigns the better he does. He now has two weeks to devote to March 4. He also outspent Mrs Clinton three to one in Wisconsin, and is raising $1 million a day (£500,000), including $36 million in January — $4 million more than thought.

He is already blanketing Ohio with campaign advertising with a huge media buy that appears to be double that of Mrs Clinton.

And he is beginning to look beyond the primaries towards a general election face-off against John McCain, a man 25 years his senior.

“He represents the policies of yesterday and we want to be the party of tomorrow,” he said on Tuesday night, as the crowd rose to its feet once more.

Mr McCain, who now talks about Mr Obama far more than Mrs Clinton, accused the Illinois Senator of being naive for advocating the hunting down of al-Qaeda members in Pakistan without having to secure Islamabad’s approval. A foreign policy spokesman for Mr Obama claimed the Arizona Republican was distorting Mr Obama’s record.

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