NORFOLK: Republican White House hopeful Mitt Romney has chosen Congressman Paul Ryan, known for advocating deep cuts in federal spending, as his running mate, his campaign announced Saturday.

The selection was first made public in a brief email message sent by the campaign to reporters saying that Ryan was Romney’s pick for vice president.

A statement shortly afterward said: “Mitt Romney today announced Wisconsin Representative Paul Ryan as his vice presidential running mate.” It did not elaborate except to add brief biographical data about Ryan, the powerful chairman of the House budget committee and a native of the Midwestern state of Wisconsin.

Ryan’s selection will be officially announced at 9:00 am (1300 GMT) during a prime photo opportunity at the USS Wisconsin, a decommissioned World War II-era battleship that also saw service during the Gulf War in 1991.

Interest in Ryan has surged in recent weeks, with conservative pundits openly urging Romney to pick him in large part because of his House-backed plan to lower taxes, slash federal spending and overhaul entitlement programs like Medicaid, the government-run insurance safety net for the poor which Ryan wants to convert into a voucher-like system to save money.

The conservative-leaning Wall Street Journal wrote in an editorial earlier this week that Ryan “best exemplifies the nature and stakes of this election,” and that choosing him would show voters that Romney was not shying away from engaging in monumental debates.

“Mr. Romney’s best chance for victory is to make this a big election over big issues,” the Journal wrote.

For months political observers had speculated that Romney would make a safe choice, with attention focusing on Senator Rob Portman of the crucial state of Ohio with considerable Washington experience that Romney lacks, or former Minnesota governor Tim Pawlenty, a Washington outsider with blue-collar roots.

But in picking the wonkish Ryan for the most important political decision of his campaign, Romney made a bold move, choosing someone who could energize the conservative base and sharpen his challenge against President Barack Obama.

The Republican flagbearer seeks to reverse a weeks-long negative trend to his campaign and boost sagging poll numbers that show Obama extending his lead on Romney nationally and holding on to leads in most of the swing states that will determine the outcome of the November 6 election.

But the choice is fraught with political peril. Obama and his Democrats have demonized the Ryan plan as giving tax breaks to millionaires while gutting much-needed federal programs and placing excessive financial pressures on middle-class Americans.

It also includes a plan to semi-privatize Medicare, the government health insurance program.

Ryan’s budget plan has made him a polarizing figure, and some experts have said he would not help Romney much among a crucial demographic: undecided and independent voters.

Ryan is a creature of Washington, elected to the House at just 28, and while that may give Romney a much-needed inside look at the workings of Capitol Hill, Congress is currently suffering from approval ratings stuck at an all-time low.

But the two men have some commonalities that may work well on the campaign trail, where Ryan has already served as an able surrogate stumping for Romney in Wisconsin, which is currently trending towards Obama.

The pair share an obsession over data and number-crunching – Ryan in his budget plans and Romney in his bottom-line business analyses.

And while Ryan has a long-term commitment toward changing the country’s fiscal trajectory, Romney has shown a steadfastness in his years-long quest for the White House.

The presumptive Republican nominee’s campaign had said the announcement could come at any time, but many experts were expecting it to be next week or even the week after, in the run-up to the Republican convention in late August.

They figured Romney might want to hold off until after the conclusion of the Olympics in London this weekend, when he and his wife Ann, who attended the Games, would have time to discuss the decision face to face.

Ann Romney has since returned and flew to Norfolk on Friday evening with her husband.

By unveiling his pick on Saturday, Romney will have his running mate by his side throughout a vital bus swing through the battleground states of Virginia, North Carolina, Florida and then Ohio, four states that Obama won in 2008 but are in play this time around.