Donna Edwards and Chris Van Hollen. (Mark Gail for The Washington Post)

Three weeks before Maryland’s up-for-grabs Democratic Senate primary, Rep. Donna Edwards has bought and broadcast her first television ad — a sharp attack on rival Rep. Chris Van Hollen.

In the ad, Edwards accuses Van Hollen of backing down against the National Rifle Association, considering cuts to Social Security, and taking money from Wall Street banks.

He is part, she implies, of “a Washington that doesn’t see and doesn’t care.”

Van Hollen, who is trailing Edwards by a statistically insignificant margin in a new Washington Post-University of Maryland poll, quickly pushed back in a debate Tuesday morning that aired on Baltimore’s WOLB radio.

“Congresswoman Edwards is unfortunately doing what people hate most about politics, which is misleading people,” Van Hollen said.

Rep. Donna F. Edwards (D-Md.) promises to stand up against the National Rifle Association and Wall Street in this campaign ad for the U.S. Senate. (Donna Edwards/YouTube)

The congressman also held a news conference Tuesday with several allies — state Attorney General Brian Frosh (D), state Sen. Joan Carter Conway (D-Baltimore), former lieutenant governor Kathleen Kennedy Townsend and gun control advocate Vincent DeMarco — all of whom criticized Edwards’s attacks as inaccurate.

Edwards is spending $156,000 to run the ad on cable and television in Baltimore, the battleground where both campaigns are focusing their efforts. Until now, she has relied on a super PAC run by Emily’s List to air ads on her behalf. Those ads have been positive, focusing on her biography and progressive record.

Van Hollen, who by the end of last year had 10 times as much cash on hand as Edwards, bought his own television time in Baltimore starting last fall, and recently bought time in the more expensive Washington media market. A super PAC run by the National Association of Realtors is also airing ads backing Van Hollen.

A new poll from The Washington Post and the University of Maryland shows the race is very close, with Edwards holding a statistically insignificant 44 percent to 40 percent lead over Van Hollen going into the April 26 primary.

The charges Edwards lays out in her ad are ones that have played out throughout the campaign to replace retiring Sen. Barbara A. Mikulski (D). But it is the first attack ad launched by either side in the heated Senate campaign.

In news releases, debates and public appearances, Edwards has pointed to comments Van Hollen made in 2012 praising a plan that would cut Medicare and Social Security benefits as a “framework” for budget negotiations. The congressman, who is the ranking minority member of the House Budget Committee, was part of a budget “super committee” tasked with forging a bipartisan spending agreement.

But no consensus was reached, and Van Hollen never endorsed changes in Medicare and Social Security benefits, according to Democratic Party leaders. What he gave his backing to was the ratio of spending cuts to tax increases laid out in the Simpson-Bowles budget plan. The plan was defeated on the House floor, and both Van Hollen and Edwards voted against it.

Van Hollen did say in that 2012 interview that he was “open to a conversation” about raising the retirement age, but separately from deficit talks. “But I think there are actually other ideas” he added, that have more merit.

In Tuesday’s debate, Van Hollen stressed that he opposed a proposal by President Obama that would have led to less-generous Social Security benefits and has been a longtime defender against efforts to cuts both that program and Medicare.

“This is not something I only talk about, this isn’t something I only vote for; I have been the [Democratic] point person on this,” Van Hollen said.

Both candidates currently support an expansion of Social Security benefits.

“He can rewrite that history now,” Edwards said Tuesday, but “he was not in the right place in 2012.”

On the NRA, Edwards is referring to a campaign-finance bill Van Hollen put forward in 2010 that would have forced outside groups to disclose more information when airing ads on behalf of a candidate. A compromise meant to improve the bill’s chances of passage excluded the NRA and the Sierra Club from the new strictures.

Many liberals, included Edwards, balked at that move. However, as Van Hollen pointed out Tuesday, many Democrats supported the legislation, which passed the House but failed in the Senate. Those who voted for it include Mikulski and Rep. Elijah E. Cummings (D-Md.). Van Hollen also pointed to his work passing gun-safety laws in the Maryland legislature before he was elected to Congress, and his work on Capitol Hill to encourage gun licensing.

“I’ve been leading the fight,” he said.

With regard to Wall Street Money, FEC reports show Van Hollen has received about $10,000 in contributions from individuals who work for Wall Street banks, a fraction of the $3.6 million he had in the bank at the end of 2015. Edwards, too, has taken small amounts of money from people who work for Wall Street banks.

Contrary to the implication in Edwards’s ad, neither candidate is taking money from bank political action committees.

Van Hollen has pointed out in debates that the Emily’s List super PAC that has committed $2.4 million to help Edwards is supported heavily by people with ties to the financial industry.