By Ted Rowlands, CNN

Cedar Rapids, Iowa (CNN) - A few months ago Sister Simone Campbell was in a brainstorming meeting trying to come up with ways to get the public's attention.

"We thought maybe we could buy an online ad,” said Campbell, the executive director of NETWORK, a liberal Catholic social justice lobby based in Washington.

Everything changed after the Vatican publicly scolded The Leadership Conference of Women Religious, an umbrella group for U.S. nuns, for allowing "radical feminist themes” to go unchecked a conferences and in their literature.

“NETWORK will be forever different because of this,” Campbell said riding through southwest Wisconsin on the “Nuns on the Bus” tour.

The scolding came in a lengthy doctrinal assessment the Vatican said was aimed at the renewal of the group of superiors who represent nearly 80% of nuns in the United States.

Campbell's religious order, the Sisters of Social Service, is a part of LCWR. But for her, the assessment was even more personal because it took direct aim at NETWORK, saying it and other parts of LCWR were too focused on social justice and not focused enough on other parts of Catholic teaching, like the sanctity of life and marriage.

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Campbell said the attention and the overwhelming support the nuns received in the wake of the Vatican’s criticism put nuns in the spotlight.

"So what we said is ‘how can we use this opportunity of the focus on us to show people what we’re all about and who we care for?’”

That’s when the idea of “Nuns on the Bus” hatched.

Support instantly flowed in for the 2,700-mile, nine-state, 30-stop bus tour that began in Iowa and will end in Washington on July 2, Campbell said.

The nuns are drawing crowds at every stop.

“That's the most amazing thing, when you walk out of the bus and you see the excitement and the anticipation," 81-year-old Sister Diane Donoghue from Los Angeles said.

Donoghue is the only nun scheduled to be on the bus the entire journey.

The nuns hope to rally support for the poor and fight proposed federal budget cuts to programs geared to help those in need.

Specifically the nuns are lobbying against the budget passed by the House of Representatives and authored by Republican Rep. Paul Ryan of Wisconsin.

The nuns even made a stop at Ryan’s Janesville, Wisconsin, district office and dropped off their “Faithful Budget Proposal” to a staffer.

The congressman has said repeatedly, and most notably in a major speech this spring at Georgetown University, that his budget is in tune with Catholic teaching.

Ryan said in a statement after the nuns dropped off their budget proposal that the national debt and outdated structures of public assistance would do more to hurt the needy than to help them in the long run.

"Economic stagnation and a growing dependency on government assistance continues to push this country toward a debt crisis, in which those who get hurt the first and the worst are the poor, the sick and the elderly, the people who need government the most," the statement said.

"To avoid a debt crisis and to restore the promise of greater opportunity and greater prosperity, Washington owes the American people bold and targeted reforms and real solutions that address today’s most urgent fiscal challenges," the statement continued.

“Congressman Ryan claiming the Catholicism mantle really set our teeth on the edge,"Campbell said. “We wouldn’t be on the road if he hadn’t done that.

“Most of the programs that Congressman Ryan is proposing to cut in the House budget are the ones that are the most effective: Head Start, food stamps, all the really important budget items that work,” Campbell argued.

As the nuns moved from stop to stop, they received a warm reception. Some cheered and others teared up with emotion when they saw the nuns.

Many said they had come to say thank you to all nuns for their decades of service.

"They’re so courageous and smart," said retired teacher and grandmother Pamela Fitzgerald, who drove 25 miles to greet the nuns in Cedar Rapids, Iowa.

"This was a wonderful idea," said Lee Mickey, a self-professed fan of Sister Simone Campbell. "This is just a way to show honor for their work."

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“This is so special” Campbell said while sitting on the bus after a visit with the Dominican Sisters of Sinsinawa in southwest Wisconsin. “Someone I just met said to me she’s been waiting for this message for years.”

As the bus rolled down the highway to the next stop, the driver notes he normally hauls around famous musicians in this rented coach.

The nuns settle in for the ride in the large leather seats, using their time between stops to send emails, glimpse up at the flat screens TVs and a grab a snack from the mini kitchen.

By now, there’s no more need for more brainstorming.

“Be careful what you pray for,” Campbell cracks, “This may be just a joke from the Holy Spirit.”