WASHINGTON -- Start with the truism: A vice presidential pick doesn't matter. Dead wrong.

Look at recent history: In 1992, a photo op with Al Gore and his family helped domesticate the image of Bill Clinton. Dick Cheney in 2000 added Dutch uncle gravitas to lighter-than-air George W. Bush. In 2008, Sen. John McCain's choice of Sarah Palin made a mockery of his claim to be the candidate with savvy and wisdom.

Now comes Rep. Paul Ryan.

Starting last Saturday on The Huffington Post and continuing more recently at Politico, anonymous and/or fallen-away Republicans and conservatives are crying havoc about Ryan.

The main reason for this is Ryan's central role in pushing a plan (which Romney supports in some respects) to turn the popular Medicare seniors' health program into a "premium support" (aka voucher) plan.

GOP operative Ed Gillespie, a veteran Washington insider who was involved in the selection and selling of Ryan, dismissed "handwringers" and remained upbeat in an interview with The Huffington Post.

"Believe me, we were going to have the debate on Medicare eventually anyway," he said. "The Democrats always attack us on it. I'd rather deal with it now than wait until they go after us in October. And we can take the offense this time by attacking Obamacare."

Indeed, the Romney-Ryan campaign launched a preemptive strike, accusing the president of "cutting" $700 billion from Medicare to fund Obamacare -- an attack strategy that worked for the GOP in 2010.

Gillespie predicted that Ryan would wear well, as people get to see him on the campaign trail. "He's really a very good candidate," he said.

It's of course more complicated than that.

In fact, conversations with professionals in both parties, inside and out of the presidential campaigns themselves, yield an evaluation that is more "con" than "pro," and by a fairly wide margin.

PRO

WHITE CATHOLIC VOTERS -- In nine of the last 10 presidential elections, the winner of a majority of the Catholic vote has won the White House. President Obama is far ahead among Hispanic Catholics; Romney needs to win among whites, but according to Gallup, he is tied with the president at 46 percent. Ryan can help with that constituency. So can Gov. Chris Christie of New Jersey, who is also Catholic and who will be the keynote speaker at the GOP convention. In Iowa, for example, it is all about producing a big Catholic turnout along the Mississippi River in towns such as Dubuque.

MIDWEST -- Ryan speaks the small-town cultural language of the Midwest, a plus not only in his own home (swing) state of Wisconsin, but in the swing states of Ohio and Iowa.

GEN X -- Tieless and with a T-shirt showing under his shirt collar, the 42-year-old Ryan is the first member of his generation to be on a ticket (President Obama, at 51, technically is a late Baby Boomer; so is 47-year old Sarah Palin). Ryan's fiscal message is aimed squarely at his peers: If we don't rein in entitlement spending, there will be nothing left for us later on. With Ryan on board, the GOP ticket can try to argue that they -- not the president -- represent the future. Expect Ryan to stress that theme when he debates 69-year-old Vice President Joe Biden.

TEA PARTY AND RUPERT MURDOCH -- Rep. Ron Paul (R-Texas) doesn't think that Ryan has cut enough from the budget, but most Tea Party types have come to admire the congressman, as have Rupert Murdoch and the Koch Brothers. That means votes -- and more Koch Kash.

WONK -- A seven-term congressman and four-term leading member of the House Budget Committee, Ryan knows the details, politics and rhetorical tricks of fiscal debates. He knows them as well as -- perhaps even better than -- the president does. If nothing else, he can give emergency tutorials to Romney.

GUY'S GUY -- Gym rat, fisherman and hunter Ryan can give Mitt 'regular guy' lessons.

CONS:

SENIORS -- Among the most diligent voters, seniors adore (and most of the rest of America likes) Medicare. By a nearly 3-to-1 margin, voters oppose cutting Medicare as a means to balancing the budget. Both versions of Ryan's plan exempt current recipients, but that isn’t going to insulate him, Romney or the GOP from what is coming. President Obama says that Romney/Ryan want to "end Medicare as we know it." The Democratic Congressional Campaign Committee, in a new attack line, merely says that the GOP wants to "end Medicare." Expect Obama and the Dems to drop the "as we know it" qualifier any day now. And while Ryan would leave Medicare alone for current seniors, his proposal to turn Medicaid over to the states could decimate Medicaid support for nursing home care. Ryan has also supported the idea of turning Social Security into a private investment system -- another unpopular idea.

HISPANICS -- Latino voters skew younger, so protecting Medicare is not a pivotal issue among that demographic. But preserving the Affordable Care Act, aka Obamacare, is. Romney/Ryan have pledged to abolish it. Ryan's views on immigration have received little attention, but they're a turn-off for most Latino voters. Ryan voted against the Dream Act and voted in favor of constructing a fence along the U.S. border with Mexico. His budget plan would whack spending on programs such as health clinics, student loans and elementary and secondary education -- all crucial concerns in the Hispanic community. Ryan could hurt the ticket in places with notable Latino communities, including Nevada, Colorado and Ohio and ...

FLORIDA -- Taken together, the combination of Ryan's positions on Medicare, Medicaid and immigration, along with local disappointment at the failure to pick Sen. Marco Rubio, makes winning Florida a much tougher climb. "We've blown it in Florida," said one top conservative, who declined to be quoted by name because of his close ties to the Romney inner circle.

SWING STATE WOMEN -- For every conservative white Catholic Ryan may pick up, he could lose swing state females in particular and urban swing voters in general. The congressman is a hardliners' hardliner on social issues, opposing federal funding for Planned Parenthood and favoring criminal penalties for doctors who perform abortions and a "personhood" amendment to the U.S. Constitution, which would open the possibility of prosecuting abortion as murder. He opposes same-sex marriage and partner benefits.

TAXES -- A key to Obama's strategy has been to paint Romney as among the top one-tenth of the 1 percent, someone who manipulates the federal tax code to enrich himself. It appears to be working. Now Ryan's budget, which proposes to abolish capital gains taxes, would benefit Romney (perhaps Ryan) personally even more.

NOT THE ECONOMY, STUPID -- Arguing about Ryan, which has taken up much of the last three days of the American political conversation, is good news for the Dems. It's three days with little talk of the 8.3 percent unemployment rate.

OBAMA KIDS -- Democrats have been justifiably worried about ginning up the same level of enthusiasm that Obama generated among young voters in 2008. Ryan, with his hardline views on social issues -- not to mention a budget plan that would severely cut education spending and loans (while leaving the defense budget entirely exempt) -- should help. Romney/Ryan would also abolish the very popular provision of the ACA that allows kids to stay on their parents' health care until the age of 26.

THE LAST 70 YEARS -- Obama advisor David Axelrod notes that the Romney/Ryan ticket is, in effect, taking on what has been a broad political consensus about the role of the federal government since the days of the New Deal. The president and his party like their chances in the role of legatees of that tradition.

THE (GOP) CONGRESS -- Yes, Ryan is only 42 and still sleeps in his Capitol Hill office on works days, but he is a congressional insider, and a congressional insider at a time when Congress is despised as a whole and in its Republican particulars. The GOP-led House is the least popular political institution in Washington, and now the president and his party can run against one of its leaders in Ryan.

GOP SEATS -- Republican strategists worry -- with good reason -- that the prominence of Ryan and his budget could cost the GOP House seats in blue or purple districts. "People are nervous, especially about the down ballot," said former GOP Chairman Michael Steele. "It wouldn't take that much of a shift for us to be in danger there."

HYPOCRISY -- Not only is Ryan a seven-term insider, he is not quite the severe budget hawk that he and Romney claim he is. He lobbied for stimulus money for his district; and his family company in Janesville, Wis., has won numerous government contracts for construction and road work. Expect that topic to come up when Romney goes after the president on the question of who built what for business. Turns out that Ryan did -- with federal money.

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