Alexandria Ocasio-Cortez, the 28-year-old first-time candidate whose victory over Rep. Joe Crowley in a New York Democratic primary Tuesday night sent shockwaves through Washington, has a few words of advice for her fellow Democrats: sharpen your message and avoid petty squabbles with President Donald Trump.

"We have to stick to the message: What are we proposing to the American people? Not, 'What are we fighting against?'" Ocasio-Cortez told MSNBC's "Morning Joe" on Wednesday. "We understand that we're under an antagonistic administration, but what is the vision that is going to earn and deserve the support of working-class Americans? And we need to be explicit in that vision and legislation, not just 'better,' but what exactly is our plan?"

"I think that's really the path forward," she added. "Getting into Twitter fights with the president is not exactly I think where we're going to find progress as a nation."

Ocasio-Cortez, a member of the Democratic Socialists of America who organized for Sen. Bernie Sanders, I-Vt., during his 2016 presidential bid, ran a bare-bones campaign and was outspent 18 to 1. She argued that Crowley had lost touch with his diverse district, both ideologically and demographically, in part because he had spent so much time in Washington.

"Our campaign was focused on just a laser-focused message of economic, social and racial dignity for working-class Americans, especially those in Queens and the Bronx. We were very clear about our message, very clear about our priorities and very clear about the fact that even if you've never voted before we are talking to you," she said.

Organization, she said, was also crucial.

"I started this race out of a paper bag. I had flyers and clipboards and it really was just nonstop knocking on doors and talking to the community," she said.

Crowley, the Queens Democratic party boss who has spent two decades in Congress, was thought to have an inside track to become the next House speaker if Democrats win back the majority in November.

Ocasio-Cortez later told NBC News that she knew how to talk to the diverse community that make up New York's 14th Congressional District, which includes parts of Queens and the Bronx, because she grew up there and watched her own family struggle.

"I’m a working-class American, my mom cleaned homes and drove school buses to make sure we could make ends meet and I spent time during the financial crisis waiting tables, so I understand what it means to be a real, working-class person in America and that is so important to have that perspective in our leadership," she said.

The district Ocasio-Cortez is running to represent is 46 percent Hispanic, 24.6 percent white, 16.4 Asian, and 11 percent black.

Sen. Kamala Harris, D-Calif., said she found Ocasio-Cortez "incredibly impressive."

"I applaud anyone who decides to run for office and put themselves out there because they want to serve the country," Harris said.

Sen. Chris Murphy, D-Conn., said that while it is tough to see his friend Crowley lose his primary, he trusted that Ocasio-Cortez was going to bring "some new energy and some youth and some vigor to Congress when she wins the general election."

"I think she's is going to be a fantastic voice for New York," Murphy added.

In a news conference, House Minority Leader Nancy Pelosi said that Crowley will be missed and stressed that the Democratic Party is a "big tent."

"Well, Joe Crowley is a very valued member of Congress, a great gentleman, as you saw in the dignity of his concession last night to Alexandria. He is, again, a valued member," Pelosi told reporters Wednesday.

She rejected the notion that Ocasio-Cortez's victory was indicative of the socialist wing of the party taking over.

"It's ascendant in that district, perhaps, but I don't accept any characterization of our party presented by the Republicans. So let me reject that right now," Pelosi said.

Ocasio-Cortez said that she ran on a message that connected with the people of her district and that's what boosted her campaign and ultimately delivered her a victory.

"I knew that our community needed a very clear voice and I think we deserved representation that rejected lobbyist funds and put our voters and our community first," she said, adding, "I felt like our party could be better, and our message could be better."

She also told NBC News that her success was also rooted in reaching everyone in her community, even those who frequently do not vote in elections.

"For so long the traditional knowledge of how to win an election is to not talk to people who don't vote, to only talk to people who have voted in the last three primaries and just try to win over those people," she said, "but I think what we showed last night is that when we speak directly to an electorate, they will come out."