WASHINGTON // Paul Ryan, a hawkish fiscal conservative, was the US Republican presidential candidate Mitt Romney's risky pick yesterday as his vice presidential running mate.
Mr Ryan, 42, a Wisconsin congressman, has been a rising star in the Republican Party. He is the head of the House of Representatives' budget committee and popular with the conservative base.
The choice is expected to energise conservatives - who have been sceptical of Mr Romney - and ensure that the presidential campaign will be fought along ideological lines. American voters are now presented with sharply contrasting visions for the next four years, particularly on government spending, welfare and taxes.
"It's not Sarah Palin. But it's a long pass down the field," said Allan Lichtman, a professor of history at American University in Washington, DC who developed a system for predicting the outcome of presidential elections that has picked the winner since 1984.
Mr Romney introduced his running mate in front of a US naval ship in Norfolk in the state of Virginia, one of a handful of states that should be crucial in November's election.
Describing Mr Ryan as an intellectual leader, Mr Romney said the Republican ticket now represented a "bold and specific plan" to avoid fiscal catastrophe.
Mr Ryan, in turn, told the crowd that the biggest danger facing Americans was a "new normal" of "diminished dreams, lowered expectations, uncertain futures".
He also drew the biggest cheer in his attempt to present the election as an ideological choice between the Republican ticket and Barack Obama, the US president.
The United States, he said, was "more than a country, it was an idea".
"Our rights come from nature and God, not from government," he said to chants of "USA, USA".
The most significant consequence of the choice probably lies in setting up an election campaign that will be fought as much over Mr Obama's less-than-stellar record in office as it will be over Mr Ryan's own proposals for addressing America's fiscal woes.
In March, Mr Ryan drafted the Republican budget proposal for 2013 that has since become known as the Ryan Plan. The plan seeks to cap non-defence government spending and includes deep cuts in welfare programmes for the elderly.
The plan was enthusiastically received in a party where spending cuts, rather than tax increases, are almost unanimously seen as the only way to address the growing budget deficit. Democrats, however, see the plan as targeting America's most vulnerable, and the Obama campaign wasted no time in reacting to Mr Ryan's appointment.
Jim Messina, Mr Obama's campaign manager, released a statement - as Mr Ryan was speaking - saying the choice of running mate meant Mr Romney wanted to take America back in time.
"Today Romney doubled down on his commitment to take our country back to the failed policies of the past."
Quoting a New York Times editorial that called the Ryan Plan "the most extreme budget plan passed by a House of Congress in modern times", Mr Messina said a Romney victory "would end Medicare as we know it and slash the investments we need to keep our economy growing - all while cutting taxes for those at the very top".
There are many advantages to having Mr Ryan as running mate, Prof Lichtman said. Mr Ryan, a father of three, is young, a Republican intellectual and a darling of the conservatives. He could fire up the Republican base in an election where turning out the vote from the party faithful may be more important than swaying independents.
But, by choosing someone who stands for so specific a budget plan, Mr Romney has given the Democrats plenty of ammunition for their campaign.
The Ryan Plan's proposed spending cuts for medical programmes for the elderly could be crucial in an election where Florida, the destination of choice for many American retirees, could be the most decisive of battle states.
"Romney can't win the election without Florida," said Mr Lichtman. "And Ryan's plan now makes him very vulnerable there."
Mr Romney is fighting a campaign almost exclusively on the economy, a strategy that is reinforced with his choice of running mate. Prof Lichtman's own system suggests that of the top 13 issues for presidential candidates to grapple with, economic issues form only two.
Prof Lichtman said that on the remaining 11 issues, which include foreign policy, national security and the candidates' personalities, Mr Obama is leading Mr Romney on nine.