* Committee vote expected Wednesday
* Competing plans to offers contrasts for campaign
* Democrats eager for debate on issue
By David Lawder
WASHINGTON, March 18 (Reuters) - Republicans in the U.S. House of Representatives will try this week to seize control of the election-year spending debate by rolling out a plan to slash trillion-dollar deficits and revive controversial reforms to the Medicare healthcare program for the elderly.
The effort from influential House Budget Committee Chairman Paul Ryan aims to portray Republicans as unafraid to face the tough decisions needed to avoid what they warn is a looming U.S. debt crisis.
He intends to contrast Republicans with what they view as a big tax-and-spend budget from President Barack Obama that would produce a fifth straight year of $1 trillion deficits and make no major changes to Medicare or the Social Security government retirement program.
Ryan will unveil the sequel to his "Path to Prosperity" budget on Tuesday, with a committee vote scheduled for Wednesday. It is expected to be considered on the House floor the following week, an aide to House Majority leader Eric Cantor said.
Although the Ryan budget resolution is expected to win approval in the Republican-controlled House, neither it nor Obama's budget plan is expected to become law. Mainly, they will be used as campaign platforms detailing policies each party wants to pursue if it wins the White House and control of Congress in November.
The main goal for Republican lawmakers is to change the subject of campaign debates from political gridlock in Congress to one where they claim an advantage - spending and deficits.
Republican aides were keeping details under tight wraps, and Ryan's appearance on CNN's "State of the Union" program on Sunday was canceled without explanation.
The committee and Republican leaders were trying last week to quell an uprising among fiscal conservatives who were demanding deeper cuts than those specified in caps agreed to with Democrats in last year' debt limit deal. Ho u se leaders were insisting on a more modest cut of $19 billion to the budget caps for fiscal 2013, which starts on Oct. 1.
But the quick committee vote on Wednesday and swift movement to the House floor - even with a critical highway bill still pending - is an indication that conflict may have been set aside and that there are sufficient votes to pass the budget plan without any help from Democrats.
MEDICARE REFORMS REDUX
Many of the 87 first-term Republicans in Congress were elected on pledges to slash wasteful Washington spending and the plan gives them an opportunity to get back on territory where they are more comfortable. Projections of ballooning U.S. debt are still a major election-year concern among voters.
"It will be a historic budget, it will alter the debt course of America," Senator Jeff Sessions, the top Republican on the Senate Budget Committee told Fox News Channel. "It will take us from unsustainability to sustainability. I'd like to see them go really far with that budget."
While Republicans aim to bring the budget back into balance without raising taxes, Obama's approach calls for higher taxes on the wealthy, while boosting investments in infrastructure and education and bringing deficits down more gradually to a sustainable level.
The Ryan plan is expected to draw a significant amount of its savings from reforms to Medicare and Medicaid, the healthcare programs for older Americans and the poor. But it will contain modifications from last year's plan, which proposed replacing traditional fee-for-service Medicare with a voucher-like system to allow seniors to purchase private insurance.
That set off a firestorm of controversy among seniors, helping Democrats to win control of a traditionally Republican House district in upstate New York last year.
Instead, Republicans aim to blunt that criticism by allowing seniors a choice between traditional Medicare and competing private plans, drawing on a proposal floated by Ryan and Democratic Senator Ron Wyden in December. They argue the changes will make the programs sustainable for future generations.
But analysts say Republicans will struggle to explain the Medicare reforms to seniors. Democrats, who are positioning themselves as defenders of the popular program, are itching for a fight over the plan..
In addition, the Republican plan is expected to shield U.S. defense spending from automatic spending cuts that kick in next January. Since a special commission failed to agree on deeper spending cuts after last year's debt limit deal, the government faces an across-the-board $97 billion budget cut.
Those cuts are expected to be shifted to other parts of the budget, including entitlements, in line with a similar proposal from the Republican-led House Armed Services Committee.
"House Republicans are continuing their efforts to reprioritize the savings called for under the Budget Control Act, because our troops and military families shouldn't pay the price for Washington's failure to take action," Ryan said in a statement last week.