Republican presidential candidate Mitt Romney’s pick of Paul Ryan as his running mate on Saturday has energized the conservative base in America which sees in Ryan a stalwart fiscal conservative but his very credentials could hurt the ticket in swing states that will likely determine the outcome of November’s election.

Ryan, a Wisconsin congressman who chairs the House of Representatives’ budget committee, was the author of the Republican budget proposal that included reform of the Medicare social insurance program which finances health care for seniors.

Ryan, in his most recent plan, would preserve Medicare as an option while offering senior citizens the possibility of receiving “premium support,” effectively a subsidy to purchase private health insurance. An earlier version of his plane privatized Medicare altogether for Americans under the age of 55.

Ryan insists that the changes are necessary to preserve Medicare in the long term. The Congressional Budget Office as well as the trustees of the program itself have warned that unless Medicare is reformed, it could go bankrupt before the end of the next decade. “Our goal is to repair the safety net,” Ryan told NBC’s Meet the Press in April of last year.

We want to have comprehensive Medicare plans available to future seniors that they can pick from and have these plans compete against each other for their benefit.

Democrats have criticized the proposal because it would “end Medicare as we know it.” President Barack Obama said in April of last year that it would leave seniors “at the mercy of the insurance industry.”

By running on Ryan’s program, Romney makes himself all the more vulnerable to attacks from the left that he would phase out Medicare. Particularly in the states of Florida, Iowa and Pennsylvania, which are considered safe for neither Democrats or Republicans, the fear of losing access to Medicare could convince elderly voters to reelect the president.

The incumbent enjoys a solid lead in Pennsylvania which hasn’t voted for a Republican in a presidential election since 1988. Given the state’s recent Democratic leanings and controversial nature of Ryan’s reform plan, “I think you can just push Pennsylvania out of battleground,” said NBC News’ political director Chuck Todd on Meet the Press this Sunday.

Similarly, in Iowa, which accounts for six electoral votes in November’s election, the older population could tip the balance in favor of president.

Florida, which wields 29 electoral votes, will likely prove decisive in determining the outcome of the election, again. George W. Bush barely won the state in 2000 but with it, the election. It is a state “that some people thought pinky on the scale for the Republicans,” said Todd. “Now, it is going to be a different conversation that is going to take place there.”

A Gallup poll conducted after Paul Ryan launched his Medicare proposal last year found 48 percent of Americans over the age of 65 in favor of his approach with 42 percent disapproving. Those numbers may well have shifted since as Democrats have vehemently criticized the Republican’s plan.

More than 17 percent of Florida’s population is over the age of 65. It has among the highest rates of retirees per capita in the nation. Last month’s polls had Romney and the president neck in neck in the state. Romney’s favorability rating among Hispanic Americans is higher in Florida than it is in other parts of the country but at 40 percent, it may not be able to make up for a potential drop in support among seniors.