GREENFIELD, Wisconsin (AFP) – Angry voters jeered and booed as the architect of the Republican budget plan tried to explain why raising taxes on the rich wouldn't help the United States deal with its deficit problems.

"It's a start!" one man shouted. "Let's do it!" another voice cried. "What about the wars?" yelled a third.

The rowdy Wisconsin town hall meeting -- and scores of others across the country -- was reminiscent of the verbal beating Democrats took from voters two years ago as they tried to explain the implications of President Barack Obama's health care reform.

It comes as the rival parties reignite a decades-old ideological clash over economic policy as they seek to tackle the nation's mounting deficits while the political climate heats up ahead of 2012 president election.

Republican House Budget Committee Chairman Paul Ryan largely kept his cool as he flipped through slides showing debt levels spiraling out of control and a "choice between two futures."

"When we say taxing isn't the solution, it isn't an ideological thing, it's a mathematical thing," the seven-term Wisconsin congressman told an overflow crowd of 650 people gathered in the assembly hall of a high school in Greenfield.

Ryan clicked through his slides until he found a chart showing that tax rates have little impact on revenues and the real revenue driver is economic growth.

When rates are too high, he told the largely disbelieving crowd, people hide their income and don't invest and businesses can't compete with foreign rivals.

"You'll shut down the economy if you just keep trying to whack up tax rates," Ryan insisted.

Teacher Kathleen MacAvaney, 48, was among those who didn't buy it. She told Ryan that he's forgetting his roots and asked him to consider a plan presented by the progressive wing of the Democratic Party that protects social programs while making deeper inroads into the debt.

"When we were growing up both of us lost a father. Both of us had mothers who took Social Security benefits to help our families get through a very difficult time," she said as her notes trembled in her hands.

"I am afraid that the safety net is getting too many holes cut in it for our next generation."

Perhaps one of the most politically risky parts of the Republican plan is to privatize the cherished Medicare health program for older Americans.

Republicans owed their November 2010 rout of Democrats in large part to Americans over 65, who went for the president's foes by a 59-38 margin four years after splitting evenly in the 2006 mid-term contest.

Ryan's plan aims to limit the potential political damage by keeping benefits intact for people currently 55 years old or over while selling younger voters on the idea that the cuts are the price of saving the popular programs.

Democrats hoping to fuel and then capitalize on the voter anger have run ads lambasting Republicans for "ending Medicare" and showing an elderly man sitting at a lemonade stand, mowing lawns and stripping to come up with the $12,500 he'll need to cover his costs.

At each of the meetings Ryan held across his Wisconsin district Thursday morning and early afternoon, Ryan asked "how many of you are 55 years of age of older?"

After the vast majority of the crowd raised his hand, Ryan assured them "this budget does not affect your Medicare benefits."

Many weren't satisfied. "What about my son?" one man asked. "I'm 54!" shouted another.

But not everyone disagreed with Ryan's plans. Applause often overwhelmed the boos and around a third of those handed the mike supported his plans, including a woman who urged Ryan to stop Congress from raising the debt ceiling and said Obama was at a "disconnect with the overall public."

Ray Gwiazdowski, 60, was among the Ryan supporters at a midday meeting in nearby Oak Creek.

"I think Paul Ryan is the only one who seems to be acting like an adult," he told AFP after the meeting.

"I think that spending is the problem... I'm a firm believer that everyone is paying too many taxes."