Republican vice presidential candidate Paul Ryan aggressively defended himself Tuesday against allegations that his GOP convention speech last week stretched the truth, saying that opponents and fact-checkers accusing him of false or misleading statements should “read the speech.”

Democrats are seizing on Ryan’s remarks, seeking to link them to his earlier errors about his personal marathon time and whether his congressional office sought economic stimulus dollars. On the campaign trail this week, Ryan also misstated the number of bankruptcies filed during President Obama’s tenure.

“While (Mitt) Romney and Ryan may want to revise the past, they can’t make up their own facts,” Obama campaign spokesman Danny Kanner said, responding to Ryan’s criticism of the president in a speech Tuesday in Ohio.

Ryan aides vigorously defended the Wisconsin Republican, accusing Democrats of trying to weave a false narrative about him to distract from Obama’s failures in office. Asked whether the heightened scrutiny of Ryan’s convention speech poses a danger for the Republican ticket, one aide, speaking on the condition of anonymity, responded: “The only danger is lazy reporters.”

With Democrats gathered this week in Charlotte, N.C., Ryan has taken on the role of attacking Obama’s record, making more than three dozen appearances since his convention speech. He has not been known to stretch the truth during his seven terms in Congress, according to colleagues and a review of his record Tuesday, but his recent slip-ups point to the perils of being thrust suddenly into the national spotlight.

During a round of appearances on morning news shows Tuesday, where he had intended to skewer Obama’s record, Ryan instead faced a flurry of questions about his remarks at the convention.

Ryan spokesman Brendan Buck disputed the contention that the candidate had made factual errors in the speech. But he acknowledged that Ryan had made small errors in other appearances. Those included a mistake about the setting in which Ronald Reagan asked his iconic “Are you better off?” question in the 1980 campaign.

“You get out and deliver a message as often as Paul Ryan has, you’re going to confuse a 30-year-old convention with a 30-year-old debate every now and then,” Buck said, referring to Ryan’s statement on Reagan. “Democrats are sorely mistaken if they think this petty name-calling is going to distract Americans from the president’s abysmal economic record.”

Earlier, Ryan told conservative radio host Hugh Hewitt that he had run a marathon in less than three hours, then later acknowledged in a statement to Runner’s World magazine that the claim was false. His time in the 1990 marathon was 4 hours, 1 minute and 25 seconds.

Ryan also acknowledged soon after his selection last month as Romney’s running mate that he had urged the Obama administration to award millions of economic stimulus dollars to his district, even though he had voted against the 2009 package. He had denied in 2010 that he ever sought stimulus dollars and repeated that denial last month in an interview with a Cincinnati television station. He later said that his office had mishandled requests from constituents.

Fact-checkers have criticized statements in Ryan’s speech to the Republican National Convention, including comments about the closing of a General Motors plant in Janesville, Wis., his hometown. The candidate seemed to suggest that the president was responsible. But the plant was largely closed in December 2008, a month before Obama took office.

Pressed about the remark during on the “Today” show, Ryan said he was not blaming Obama for the plant’s closing but rather for not helping, as he promised, “to lead an effort to retool plants like the Janesville plant to get people back to work.”

“Read the speech,” Ryan said. “What I was saying is the president ought to be held to account for his broken promises.”