We now know all major party candidates seeking our country's top two offices in the Nov. 6 election. President Barack Obama and Vice President Joe Biden are running against Mitt Romney and Paul Ryan, a conservative Wisconsin congressman who joined the Republican ticket last weekend. By selecting Ryan, Romney "intensifies the debate over the size and role of government," the New York Times says.

That's because Rep. Ryan, as House Budget Committee chairman, is the main architect of a Republican budget plan to cut federal taxes and spending. "Higher unemployment, declining incomes and crushing debt is a not a new normal. It is a result of misguided policies," Ryan said Saturday in Norfolk, Va., where Romney announced his choice. Ryan also is a leading advocate of sweeping changes to Medicare health insurance for retirees.

He proposes transforming Medicare into a program in which future seniors would receive government checks to buy private health insurance. The government now pays doctors, hospitals and other health care providers directly for services covered by Medicare. Ryan and others say the change is needed to keep the program from financial collapse. Critics predict the change would impose ever-increasing costs on seniors and "end Medicare as we know it,” as the president's campaign manager said Saturday.

The new running-mates will be nominated formally at the Republican National Convention in Tampa, Fla., at the end of this month. Romney is a former Massachusetts governor who grew up in Michigan as the son of that state's governor. Ryan is a fifth-generation native of Janesville, Wis., who first won his House seat 14 years ago. His wife, daughter and two sons were at the big announcement in Virginia.

Paul Ryan says: "We can't afford four more years of this [economy]. Politicians from both parties have made empty promises which will soon become broken promises -- with painful consequences -- if we fail to act now." -- Aug. 11 announcement remarks

Backer says: "He manages to bring both gravity -- he’s dead-serious about fixing both the economy and the budget -- and excitement to the ticket." -- Rachael Larimore, managing editor at Slate news site

Critic says: "Mitt Romney has chosen a leader of the House Republicans who shares his commitment to the flawed theory that new budget-busting tax cuts for the wealthy, while placing greater burdens on the middle class and seniors, will somehow deliver a stronger economy." -- Jim Messina, Obama campaign manager