I expected Mitt Romney to pick Bob McDonnell as his running mate. I’ve said repeatedly that my two choices were either Bobby Jindal or Paul Ryan, but I expected Bob McDonnell. I’m delighted I got who I wanted and not who I expected. Paul Ryan is a daring choice.

I’ve talked to a lot of Republicans over the weekend and 48 hours after Paul Ryan stepped out at the USS Wisconsin to become Mitt Romney’s running mate, there is a rumbling of nervous excitement, but also some serious worry. There is a pretty clear consensus that Paul Ryan as the veep pick was actually a dangerous and very risky pick signaling Romney’s internal polling might not be so great in swing states. At the same time, everyone largely acknowledges that there is, in the greater risk of the pick, a greater reward if the Romney-Ryan ticket wins.

Why dangerous and risky?

First, picking Paul Ryan ties MItt Romney to the Ryan budget plan. This now turns the election into a choice between Barack Obama’s way forward and the Romney-Ryan way forward. The race is no longer a referendum on Barack Obama’s job. No one doubts Barack Obama has a better chance when the election is a choice between two competing visions and not just a referendum on his failure.

Second, it muddies the message. Instead of a race focused on the economy, we are suddenly entering a race about the economy and medicare, medicaid, and social security without being able to throw Obamacare at Barack Obama.

Third, because of the first two, Florida is now even more in play and several Republicans I talked to say it makes Florida more friendly toward Barack Obama. This relates to the senior vote and a suspicion the Romney team cannot competently execute counter measures against the coming demagoguery.

Why the reward if they pull it off?

Everyone knows what Paul Ryan brings to the table. If Romney-Ryan wins, suddenly they can make a real case for entitlement reform, smaller government, and debt reduction based on spending cuts, not tax increases.

Ben Domenech’s thinking sums up a lot of what I’ve been hearing and I share his thinking:

The decision to pick Ryan is not a safe one, however. And it is a definite break with the path that Team Romney has adopted to this point—one which adopted the sit-on-your-hands restraint Ryan spoke of in 2011 with such disdain, essentially attempting to make the first Friday of every month Romney’s running mate. And in accepting this advice and choosing Ryan, the Romney Team is indicating that they may very well be more desperate than they let on. This is not a pick you make if you are confident you are ahead or tied. It is the kind of pick you make when you think you are behind.

Because I do think Romney is behind—in the sense that if the election was today, I do believe he would lose—I think it is a selection worth the risk.

Most everyone I talked to was excited by Paul Ryan as the choice, but they all shared apprehension. The chief apprehension is very simple — there is a growing sense among Republicans that Mitt Romney’s team has a repeated and serious failure to execute.

Paul Ryan, as the veep pick, is a recognition of this. Romney needed to do something beyond a boring pick to get momentum back. More than that, Paul Ryan is a brilliant spokesman on budget issues and on economic issues. He understands the free market and is not afraid to zealously advocate for it and defend it.

The Romney team is going to have to sell this. They’re going to get hit hard on “mediscare” and will need to be able to nimbly counter-punch. Paul Ryan has several times in the past year already made the best case — Barack Obama has had one term and failed to even deal with these issues.

If the Romney team can execute a strategy that ties economic reform with entitlement reform, they’ll have a winning play against Barack Obama, whose singular achievement in office remains a failed healthcare plan that will wreck our economy and our healthcare system in the process.

Again though, tempering all the excitement many Republicans have over Paul Ryan as the veep pick is a lingering doubt that the Romney team really has what it takes.