(CNN) - Mitt Romney on Thursday pushed back against Senate Majority Leader Harry Reid's allegations that the presumptive GOP nominee has not been paying his taxes.
"It's time for Harry to put up or shut up," Romney said on Sean Hannity's radio show.
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In a Huffington Post interview published Tuesday, the leading Democrat said that an unnamed investor with Bain Capital, Romney's former private equity firm, told Reid in a phone conversation that Romney had not paid taxes for a decade.
Reid stood by the allegations on Thursday while speaking on the Senate floor.
"The word's out that he hasn't paid any taxes for 10 years," he said. "Let him prove he has paid taxes because he hasn't."
Democrats and President Barack Obama's re-election campaign have repeatedly called for Romney to release more tax documents to answer any questions about his financial portfolio.
Romney has made public the full 2010 tax return and an estimate for 2011, with a pledge to release the full year once it's complete. He filed an extension for an October deadline.
Critics have hit back against Reid's comments this week, faulting him for making claims based off an anonymous source.
"Harry's gonna have to describe who it is he spoke with because of course that's totally and completely wrong," Romney said Thursday in the radio interview. "It's untrue, dishonest and inaccurate. It's wrong. So I'm looking forward to have Harry reveal his sources and we'll probably find out that it's the White House."
Mirroring Romney's comments, senior campaign adviser Eric Fehrnstrom described Reid's comments as "shameful, pathetic, baseless and untrue" and argued the majority leader, with the help of the Obama campaign, was attempting to "engage in McCarthy-like accusations about Mitt Romney."
"Four years ago Barack Obama said he was going to come to Washington and change the politics. Instead the Obama campaign has turned into a bottomless pit. Every day they reach a new low," he said Thursday on CNN's "The Situation Room."
Adding on, Fehrnstrom said Romney has "never zeroed out his tax liability" and "has always paid 100% of what was owed."
After Romney's interview on Hannity's radio show, the majority leader responded in a statement and said he is not backing down from his remarks.
"As I said before, I was told by an extremely credible source that Romney has not paid taxes for ten years. People who make as much money as Romney have many tricks at their disposal to avoid paying taxes," he said.
Reid argued Romney is "hiding something" and called on the presumptive GOP nominee to release more taxes.
"When it comes to answering the legitimate questions the American people have about whether he avoided paying his fair share in taxes or why he opened a Swiss bank account, Romney has shut up. But as a presidential candidate, it’s his obligation to put up and release several years’ worth of tax returns just like nominees of both parties have done for decades," Reid said.
According to a source familiar with Reid's thinking, the majority leader, a former boxer, considers himself a political street fighter now, willing to throw a punch and get hit back big time for a cause. In this case, the cause is making sure the topic of Romney's tax returns remains in the news, and in the campaign narrative.
The source said Reid is "happy to mix it up and put this back in the news" and added the "finger waggers of the Acela corridor won't dissuade him from speaking his mind."
Reid, the source said, is unconcerned about the hits he is taking on making unsubstantiated claims, because the Democratic base is fired up. The source says they know that anecdotally. It's not an accident that Reid said this to the Huffington Post, a friendly outlet, and did so as Romney was returning from his overseas trip.
"What happened when Romney returned? The first story he has to deal with is his tax returns," the source said.
One of Romney's biggest surrogates, Sen. John McCain of Arizona, came to Romney's defense on Thursday, saying Reid may have "gone over the line."
"I've known Sen. Reid for many, many years, and occasionally he displays some rather erratic behavior," McCain said on CNN's "Anderson Cooper 360." "To accuse someone of doing something without a shred of proof–that the allegation has any substance–is really something I, frankly, don't understand."
McCain, whose 2008 presidential campaign reviewed Romney's tax records as they considered him to be the vice presidential running mate, said last month he can "personally vouch" that there was "nothing disqualifying" in the tax returns of the presumptive GOP presidential nominee.
On Thursday, he urged Reid to come "forward" with his source.
"I think politics are tough. I enjoy the give and take but I think Harry might have gone over the line," McCain said.
Later, while visiting a fruit stand with his mother in Florida, Ryan responded to the negative reaction in the room.
"Entitlement reform has unfortunately been made very partisan by partisans, and so I have gotten that kind of reaction and unfortunately it's what we come to expect because the politics of reforming entitlements has become very bitter and it's very unfortunate," he told reporters in Lakeland.
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They say the IRS doesn't mess with people like Mitt Romney because they have the resource with their tax lawyers and accountants. They say IRS will audit you if you can't fight them and personally I couldn't fight them submitted to whatever they said I owed.
The source is Dick Cheney
Pfft, what faith can be found?
To Thinkagain...why then is his social security card issued in Connecticut when he has never lived there?
He needs to Clear this matter up once and for all and release All of his tax returns Posthaste! If there is nothing that would worry the presumptive Republican nominee then why not just come out and say - Here It is In Full! That's all it takes. The longer he waits in releasing them the worse it looks for him! In the meantime, since he apparently doesn't want to release his tax returns, can one honestly blame the Democrats for wanting this matter cleared up? Of course not! Romney owes at least that much to the American people at this time if he wants the nation's top job otherwise he's toast! Just how hard can it honestly be to show the American people he wants to lead his tax returns?
If Romney is dirty now ............ He will be dirty as a President too . ........ He refuses to go by the rules already .
How about a nice deal – if Romney shows his tax filings and proves he has paid taxes, Reid steps down from the senate and retires from politics and makes a donation in the amount what Romney paid as taxes to a charity of Romeny's choice. If Harry proves otherwise, Romney steps down from being the republican nominee. (and may end up paying a fine if found guilty of tax fraud)
'We the People" to Romney, Put up your income tax forms and we will shut up!
Its either time to poop or get off the pot Mr. Romney. You wanted to see the birth certificate, you saw it. Man up and show your tax returns....
Tax returns are one etch-a-sketch that Mr. Romney cannot shake. That's why he doesn't want to tell us about them.
Permanent damage exists in them thar tax returns.
Reid should neither put up, nor shut up. Romney can demand whatever he wants.
Fair deal, I think.
Once again Reid stoops to a new low, for a congress that already is in the pits of public opinion. Let's compare Mr. Reid's tax return with Romney's and see who paid their "fair share". How about it Mr. Reid, willing to publish the last 10 years of your tax returns for everyone to pour over and scrutinize?
Mitty this is very easy > release the last 10 years tax returns and prove Reid wrong.
Mitty you filed for an extension to complete you 2011 tax return. If, you can't put your own finances in oder because in a year you are running for the highest office in the land you can't file your own tax return on time how can we expect you to put the country's finances in order?
This is.clearly a display of arrogance and lies of dem's political limbo.
Mitt actually hasn't released a full Tax Return. The 2010 one isnt a complete Tax return and the 2011 one is less than half a Tax Return.
So when did we get to guilty until proven innocent? Its obvious Reid has made this up to try and coax Romney into releasing tax info. How many years of tax returns has Reid made public? Or Obama?
Mitt doesn't pay taxes like you and me,
He milks the system,
He lives for free.
He only likes welfare
When it goes to the rich
Prepare to bend over
And become Romneys b!$&@
I believe it is a felony to have other peoples tax info so if Reid does have Romneys tax info he has commited a crime and should be charged along with the one who gave the tax information to Reid as well same on both of them!
if Romney has done something illegal or wrong as the democrats claim, why isn't ge being prosecuted? this is purely about intellectually bankrupt liberals needing to deflect from the fact Obama said himself he should be fired, and only serve one term tha absolute failure he's been.
Where's Donald Trump now? Mitt, release the taxes and show all the truth!
Mitt has already released his 2010 and 2011 tax returns. both of which clearly show Romney paid significant amounts of income tax in the last two years. Yet Harry Reid doubles down on his slander saying Mitt hasn't paid any taxes in ten years. So why does anyone even entertain Harry Reid's obvious lies. May I suggest Harry Reid keep handfuls of baking soda or a similar flame retardant in his trouser pockets. To show Harry Reid has bovine diaria of the mouth only requires one tax return from Mitt showing any taxes were paid in the last ten years. Yet we already have two years worth of Mitt's taxes. It is a disgrace that Harry Reid would use his position as Senate Majority Leader of the US Senate and it's podium to launch obvious slanderous lies to assist the failing campaign efforts of Obama. A very sad day in America indeed!
What is so hard about showing your tax return for the last 10 years unless you have something to hid, for God sake romney you are running for president, so get rid of the rumors, show your tax return and put an end to all this, again unless your hiding something. Zack
I hope Reid won't back down and will continue to insist on Romney's accountability. I see Romney as a spoiled brat, usually getting his way. I hope his bluff has finally been called. To back off always allows a serial liar to strike again. You have him where it can hurt. Tighten the grip.
How about YOU shutting up, Mittens? Put the tax returns out there before you've had a chance to pretty them up!
I was told by an extremely reliable Nevada resident that Senator Harry Reid is related to Richard C. Reid, the shoe bomber. Since Senator Reid has not shown any proof that he isn't related then he must be hiding something.