Mitt Romney took a second hit from a New Hampshire newspaper Wednesday, with the statewide Manchester Union Leader urging voters to scoff at his candidacy. The editorial follows a similar Concord Monitor piece over the weekend.

Both Granite State newspapers charged the former Massachusetts governor with flip-flopping and teased at his Achilles' heel -- the image he has fought to overcome of an insincere, over-rehearsed, plastic candidate.

"Like a lot of people in New Hampshire, we wanted to believe Romney. We gave him the benefit of the doubt. We listened very carefully to his expertly rehearsed sales pitch. But in the end he didn't close the deal for us. Now, two weeks before the primary, the same is happening with voters," the Leader wrote.

Click here to read the Leader's anti-endorsement of Romney.

Romney responded to the article Wednesday afternoon in Henniker, N.H., contesting the Leader's assessment and highlighting his recent endorsement by conservative magazine National Review, as well as those by New Hampshire Sen. Judd Gregg and Judge Robert Bork.

"I'm pleased with the endorsements I've had ... But of course I can't get all of the endorsements. I'm going to try and get all I can. But ultimately the endorsement I really care about is the endorsement of the voters of New Hampshire," Romney said.

And he defended the consistency of his positions while in office, saying, "But if you look at my record as governor you can see my positions are the positions I carried out as governor. There was no change."

In its editorial, the Leader touted Arizona Sen. John McCain, whom the paper already endorsed and who has recently re-surged to pose a stiff challenge to Romney in New Hampshire. A Boston Globe poll of 410 likely Republican voters from Dec. 16-20 showed Romney with 28 percent and McCain with 25 percent in New Hampshire. The margin of error was 4.9 points. New Hampshire holds its presidential primary on Jan. 8

"Romney has all the advantages: money, organization, geographic proximity, statesman-like hair, etc.," the Leader said. "But he lacks something John McCain has in spades: conviction. Granite Staters want a candidate who will look them in the eye and tell them the truth. John McCain has done that day in and day out, never wavering, never faltering, never pandering. Mitt Romney has not. He has spoken his lines well, but the people can sense that the words are memorized, not heartfelt."

The Union Leader ridiculed Romney for the recent flap over his claims regarding his father's role in the civil rights struggle. While his father George Romney's civil rights advocacy is unquestioned, Mitt Romney stirred up skeptics when he said during a major speech on religion and politics that he saw his father and King marching together. Romney later admitted he was being figurative, and that he didn't actually see the two together, but stood by the statement all the same -- even though historical accounts do not place the two together at the same march. Politico reported Friday that two witnesses recalled seeing the two together, but the Boston Phoenix reported the next day that the witnesses were mistaken.

After the Concord Monitor lashed out at Romney Sunday for being a "phony" and changing position on issues such as abortion when he ran for president, Romney's campaign brushed off that paper's editorial board "as a liberal one on many issues."

And the campaign pointed to his endorsement Sunday by the Sioux City Journal in Iowa, where caucuses will be held Jan. 3.

The campaign cannot assert the same "liberal" claim with the Leader, the only statewide s in New Hampshire. But the fact the paper has already endorsed McCain somewhat lessens the sting, since the Leader has a history of going after the rivals of its endorsed candidate.

FOX News' Carl Cameron and Shushannah Walshe contributed to this report.