By Andy Sullivan
WASHINGTON (Reuters) - Mitt Romney tried to silence questions about his taxes as the Republican presidential candidate limped to the end of a brutal week on Friday, while his running mate faced boos and heckling at a campaign stop.
Slipping poll numbers, fundraising woes and a secretly recorded video that shows Romney writing off half the electorate as "victims" have prompted many Republicans to question whether their candidate is losing a race that had seemed winnable only weeks ago.
Romney's wife Ann asked Republican critics to cut her husband some slack and unite to defeat President Barack Obama on November 6.
"This is hard. You want to try it? Get in the ring," Romney's wife, Ann, said on an Iowa radio station late Thursday.
Romney aims to make the election a referendum on Obama's handling of the sluggish economy, but he has been knocked off message by a string of missteps over the past week and a half. New figures show Romney also trailing Obama in fundraising, an area that was expected to be a strong point of his campaign.
Romney said he was within striking distance of Obama and his campaign did not need a major reversal of fortunes.
"It doesn't need a turnaround. We've got a campaign which is tied with an incumbent president," Romney told CBS's 60 Minutes.
With early voting already underway in three states, most opinion polls have been moving in Obama's direction.
A Reuters/Ipsos daily tracking poll showed Obama stretching his lead over Romney to 6 percentage points. The Democrat now leads Romney 48 percent to 42 percent, up 1 point from the day before.
Other polls show Obama leading in many of the battleground states that are likely to decide the election. A Wall Street Journal/NBC poll had Obama leading by eight points in Iowa and five points each in Colorado and Wisconsin - states that Romney must carry if he is unable to close the gap in other battleground states like Virginia and Ohio.
Another poll by Purple Strategies showed Romney leading by only three percentage points in Arizona, a state that had been thought to be safely in the Republican column.
"WORST WEEK IN WASHINGTON" - AGAIN
A Washington Post column widely read by political junkies gave Romney the dubious award of "Worst Week in Washington" for the second week in a row.
Romney has campaigned on the premise that his success in business makes him a better bet than Obama to help the country recover from the deepest recession since the 1930s. The Obama campaign has attacked the former private equity executive as a job-killing corporate raider who has little sympathy for the concerns of average voters.
Seeking to lay to rest Democratic charges that he paid no taxes in the past, Romney released a letter from his accountants saying that the lowest annual effective rate he paid was 13.6 percent between 1988 and 2009. Over that period, his average federal tax rate was 20.2 percent, the accountants said.
That did not satisfy the Obama campaign, which questioned why he still refuses to release the actual tax returns for those years.
Romney's vice presidential running mate, meanwhile, was booed and heckled by members of the retiree group AARP as he laid out the Republican ticket's case for repealing Obama's healthcare law and partially privatizing the Medicare health plan for retirees.
"I had a feeling there would be mixed reactions," Ryan said.
Ryan's dramatic plan to slash spending and overhaul Medicare have made him a hero to conservatives, but polls indicate that voters trust Obama more when it comes to protecting the popular health program.
Romney's 20 point-edge among voters over 65 has eroded over the past several weeks to the point where the two candidates are effectively tied, according to Reuters/Ipsos polling data.
Obama was greeted more warmly by AARP members at the New Orleans event as he told seniors that Romney and Ryan's health plan would force them to pay more for their medical care.
"I don't consider this approach bold or particularly courageous. I just think it's a bad idea," he said.
AARP, formerly known as the American Association of Retired Persons, claims 37 million members and is regarded as one of the most powerful lobbying forces in Washington.
Ryan traveled to New Orleans to speak to the association, while Obama addressed them via video from Virginia.
Romney, meanwhile, traveled to Las Vegas to raise money.
The secretly filmed video of Romney, released earlier in the week, showed him denigrating people who receive government handouts or pay no federal income taxes - a group that includes retirees who receive Social Security and Medicare.
"Given the conversations that have been out there in the political arena lately, I want to emphasize Medicare and Social Security are not handouts," Obama told the AARP group. "You've paid into these programs your whole life, you've earned them."
(Additional reporting by John Whitesides, Matt Spetalnick and Lisa Lambert; Editing by Alistair Bell and Jackie Frank)