Democratic Senate candidate Elizabeth Warren today won a clear road to an Election Day showdown with U.S. Sen. Scott P. Brown, capturing the Democratic nomination with enough votes to avoid a primary election with her Democratic challenger Marisa DeFranco.

“I've got just one thing to say: Are you ready?” Ms. Warren shouted from the stage of the MassMutual Center to screams of affirmation from delegates after it was announced that she won 95 percent of the delegate votes for the nomination. “Are you ready to stop the Republicans from taking over the U.S. Senate?” she asked.



Ms. DeFranco, a Middleton attorney who campaigned with little money for more than the past year, failed to get the required 15 percent of the delegate votes needed to force a primary for the Democratic nomination.



State Democratic Chairman John Walsh said that until today, no candidate had ever exceeded 85 percent of the delegate vote in a contested nomination process at a state convention to eliminate a primary challenge.



Ms. Warren, running for office for the first time, vowed to reclaim “the people's seat” from Republican Sen. Scott P. Brown and zeroed in on his record in an address that brought the crowed of approximately 4,000 delegates to their feet. She barely mentioned Ms. DeFranco and remarked that voters did not get what they expected when they elected a Republican to the Senate four years ago. Ms. Warren said voters thought they were sending “a decent guy” to Washington.



“But boy, did he let us down. In no time at all, he chose Wall Street over Main Street, millionaires over the middle class, and big oil over big ideas,” Ms. Warren said.



She criticized his votes against three job bills offered by Democrats, said he voted twice to double student loan interest rates and said he personally negotiated to weaken bank rules while others were working to rein in Wall Street. She said she will stand for families and for creating jobs as well as women's rights.



“We stand for women, equal pay and access to birth control,” she said, adding, “I never thought I'd need to say that in 2012.”



Ms. Warren did not dwell on the huge controversy that has erupted over her claims of Native American ancestry except to bash Mr. Brown for using it to answer the question of how he will get re-elected.



“His answer is to talk about anything except how he votes on jobs, education, the environment, oil subsidies or special deals for Wall Street. His answer is to talk about my family and tell me how I grew up,” Ms. Warren said, referring to Brown comments this week that she should not believe she has Native American ancestry because her parents told her so. “I say if that is all you've got, Scott Brown, I'm ready,” Ms. Warren shouted out to the cheering arena.



Ms. DeFranco also targeted Mr. Brown in her speech and told delegates the party would be stronger for having gone through a primary contest. She said in 16 years of running a federal immigration law practice, she learned real world lessons that will help her “fight for everyday people” against the powerful.



Ms. DeFranco said she was up for the fight. “Make no mistake. Scott Brown is going to make this a street fight. We need a candidate who can take a punch and come out fighting with ideas and solutions,” she said. Addressing concerns among some delegates that a primary will distract from a focus on beating Republicans, Ms. DeFanco told delegates, “Trust in the voters.”



“Let's have a good and healthy primary and go after Scott Brown all summer long together. We will be the stronger for it,” she said. But the delegates disagreed, opting to engage the final fight from the start.



Mr. Walsh said deciding whether to give Ms. Warren a primary-free race was not the only game at the convention.



“What this convention is really about is connecting with the organizers,” Mr. Walsh said, noting that the estimated 4,000 delegates are the key to getting votes all over the state.



He said Ms. Warren will get a huge benefit from the governor's recent endorsement of her campaign. “What Deval Patrick is going to add to any campaign that he supports is a remarkable focus on a door-to-door effort. No one in America knows how to do it better than he does,” the party chairman said.



“We are opening up coordinated campaign offices all across the state now and through the summer” and making plans for candidates to share data, he continued. “Most of our candidates share the same database. They are segmented, but when it comes together on Election Day, we can easily, if those candidates are willing, merge that information to make sure we go and get everyone who will vote for a Democrat,” Mr. Walsh said.



Worcester City Councilor William J. Eddy, who attended as a delegate, said, “It's really a Democratic rally, saying we are here and we are ready,” Mr. Eddy said.



Mr. Eddy said he believes the Warren campaign should move past the heritage controversy that has been stoked by Republicans and the Brown campaign. “It's a bit unfair for a woman who built her entire life trying to build integrity in everything she has done, so I am sure she finds herself in waters she is unaccustomed to,” Mr. Eddy said. “Has she handled it the way a seasoned pro would handle it? Probably not, but at some point she needs to say this is not what the people of Massachusetts care about,” he said.



Lt. Gov. Timothy P. Murray of Worcester gave the convention a spirited rally speech, calling on them to get “all in” to back Democratic candidates this fall and “to elect a new Senator from Massachusetts who will say no to [Sen. Republican leader] Mitch McConnell and the politics of gridlock and division.”



Also offering a speech that got conventioneers on their feet was Gov. Deval L. Patrick, who put his name and campaign organization behind Ms. Warren on Wednesday. Mr. Patrick zeroed in on partisan issues, saying the state had 16 years of Republican governors. Since Democrats took over the governor's office, he said the state went from 47th in job creation to lead the nation in economic competitiveness, student achievement, health care coverage, energy efficiency and veterans services.