Badey is challenging Meehan in a district centered in Delaware County; Trivedi is taking on Gerlach in a Chester County-based district, and Boockvar opposes Fitzpatrick in a Bucks County-centered race. All three challengers seized on budgets Ryan has crafted as chairman of the House Budget Committee.
The GOP congressmen fired back by accusing President Obama and his Democratic allies of being the ones to cut Medicare. Ryan and his backers, they argued, would save the program by controlling its costs.
"Pat Meehan is the only candidate in this race working to save Medicare for today's seniors and future generations," Meehan spokesman John Elizandro said.
In 2011 and this year, Meehan and the other two incumbents joined most of their Republican colleagues to back Ryan's plans, supporting budgets that called for cutting taxes and spending while slashing college aid and programs for the poor and, most controversially, reshaping Medicare for future recipients.
Medicare is a powerful issue, particularly in Pennsylvania, which has 2.3 million beneficiaries, fifth most in the nation, according to the Kaiser Family Foundation. (The Ryan budget would not affect current recipients, but the numbers give a sense of the issue's reach.)
"The Democrats are going to savage the Republicans on this," Franklin and Marshall College political scientist G. Terry Madonna said. "They recognize the potential upside to this."
But Madonna cautioned that the incumbents have some breathing room, thanks to last year's reapportionment process that added GOP turf to all three districts. "The question is whether it's enough to change the context of these campaigns. At the moment, I don't see that happening," he said.
The Democrats, though, calculated that GOP presidential nominee-to-be Mitt Romney's choice Saturday of Ryan as his running mate was a chance to pick on voting records that are plain to see.
Ryan and Fitzpatrick "have been working hand in hand, day after day, to fight for billionaires and special interests, all against the best interests of middle-class families," Boockvar said. Trivedi said Ryan and Gerlach "might be working out with each other, but they're not working for the middle class."
Fitzpatrick, Gerlach, and Meehan had no public appearances Monday and did not make themselves available for interviews. Their campaigns, though, said the Ryan plan would preserve Medicare and cut the nation's growing debt. They charged that the administration has taken $700 billion from Medicare without a peep from their Democratic challengers.
"The more Boockvar fumbles with the Ryan budget, the more it will become clear that the government-run health-care plan supported enthusiastically by her guts $700 billion from Medicare while putting the bureaucrats in between doctors and patients," wrote Faith Bender, Fitzpatrick's campaign manager.
The Gerlach campaign said Trivedi supports "ending Medicare as we know it."
Obama's Medicare savings, though, are also included in the Ryan-crafted budget. The savings would largely come from health-care providers, not patients, according to independent analysts.
Under Ryan's most drastic Medicare plan, on the other hand, "most elderly people would pay more," according to the nonpartisan Congressional Budget Office.
Ryan has since eased that proposal, but House Republicans cleared the idea in 2011, and it remains a lightning rod for criticism.
Democrats also took aim at South Jersey U.S. Rep. Jon Runyan, who also voted for Ryan's budgets, sparking a similar back-and-forth in another district Democrats have targeted.
While Democrats were the aggressors Monday, the National Republican Congressional Committee released a statement saying: "We want this fight."
On that, both sides seemed to agree.
Contact Jonathan Tamari at firstname.lastname@example.org. Follow on Twitter @JonathanTamari.