FACTBOX: Presidential candidates' ideas on economy

(Reuters) - President George W. Bush has proposed a $150 billion plan to help stimulate the ailing economy.

Worries that a recession may be looming have prompted several of the candidates in the U.S. presidential race to unveil plans to give the economy a lift. Here are their ideas:

DEMOCRATIC U.S. SEN. HILLARY CLINTON

The New York Democrat has proposed a $70 billion package to stave off a possible recession, including $40 billion in spending for heating assistance, an extension of unemployment insurance and investments in energy efficiency.

The other $30 billion would go toward helping low-income families hit by the mortgage crisis.

A second phase of the package, which would total an additional $40 billion, would be triggered if the economy failed to respond. That would pay for tax rebates for low- and middle-income workers.

DEMOCRATIC FORMER U.S. SEN. JOHN EDWARDS

The former Democratic senator from North Carolina has proposed a $25 billion job creation plan with the possibility of $75 billion more if there is more evidence the United States is entering a recession.

The plan calls for investing in clean energy infrastructure, increasing federal aid to help states avoid cutting programs that help families through hard times, reforming unemployment insurance and tackling housing crisis.

DEMOCRATIC U.S. SEN. BARACK OBAMA

The Illinois Democrat's $75 billion plan includes an immediate $250 tax cut for workers that would double if the economy worsens.

Older Americans would receive a one-time $250 bonus in their Social Security checks that would also double in a severe downturn. Obama would offer assistance to homeowners facing foreclosure and aid to states hit by reduced tax revenues. He would also extend unemployment insurance for laid-off workers.

REPUBLICAN MITT ROMNEY

The former Massachusetts governor has proposed a stimulus package centered on permanent tax breaks, rather than temporary measures, expected to cost $250 billion.

Romney wants to permanently cut the rate for the lowest income tax bracket to 7.5 percent from 10 percent, retroactive to 2007; eliminate Social Security payroll taxes for workers over 65; and eliminate capital gains and dividend taxes on households earning less than $200,000 a year.

He would also permanently reduce the corporate tax rate to 20 percent from 35 percent over two years and allow businesses to depreciate the value of new equipment purchases faster.