Murphy garnered the support of 76 percent of the 1,823 delegates, calling it a "resounding margin" and a good indicator for a general election victory.
"I tell you, with this kind of enthusiasm, I know we're going to make sure that a Democrat gets elected to the United States Senate," he told the cheering delegates, who gathered in a gymnasium at Central Connecticut State University. He said the state Democratic Party hadn't seen such a lopsided convention win in a long time.
But Murphy will first have to defeat his chief rival for the party's endorsement, former Secretary of the State Susan Bysiewicz. She secured enough delegates - 24 percent - to win a spot on the Aug. 14 primary ballot and vowed to continue her campaign. Bysiewicz needed 15 percent of the delegates to meet the threshold.
"I support the Democratic voters of the state having the opportunity to make a decision about who can best stand up for our party and serve in the United States Senate," Bysiewicz said. "So I strongly believe that a larger group of people making a decision is better and I fought my entire career in public service for the right to have more people participate."
Murphy, a 39-year-old father of two from Cheshire, said he was surprised Bysiewicz didn't win more support at the convention, given her years of public office. He said he would prefer to avoid a primary, especially if the Republicans endorse wealthy, former wrestling executive Linda McMahon at their convention on Friday, but will now "have to wage a two-front war."
McMahon spent about $50 million of her own money on her failed 2010 Senate race. Murphy has raised about $3.5 million for his Senate bid, while Bysiewicz has raised $1.75 million.
McMahon and former U.S. Rep. Christopher Shays are the two front-runners for the GOP's endorsement. No matter who wins, both plan to continue on with a primary challenge.
Murphy went into Saturday's convention as the clear front-runner. A former state senator, Murphy has worked to successfully secure the backing of key unions across the state as well as top state Democrats, most notably Gov. Dannel P. Malloy, who nominated Murphy at Saturday's convention.
Malloy referred to Murphy, 39, as "a great guy" and a "great man" and predicted the congressman will be "that line between the Republicans and what we want to do for our nation."
The governor has gotten personally involved in the intra-party battle, calling delegates on the phone and publicly suggesting Bysiewicz should not wage a primary.
The 51-year-old Bysiewicz, a mother of three from Middletown, said she has never been popular with "the party insiders" because she has a record of standing up for things "that make insiders uncomfortable" such as campaign finance and ethics reform. But she said those are issues that voters care about.
Malloy took issue with being called a party insider, calling Bysiewicz "the ultimate insider who has run for more offices in a period of two years." He told reporters that for her to call someone else an insider, "that's chutzpah." Bysiewicz ran for governor and later attorney general in the 2010 election cycle. She later had to drop out of the attorney general race after the state Supreme Court ruled that she was not qualified to seek the office because she did not have the requisite amount of experience as a practicing attorney.
This is not the first time that Bysiewicz has lost the party's endorsement yet continued on to wage a primary.
In 1998, she lost the party's endorsement for Secretary of the State to former state Rep. Ellen Scalettar. Despite a phone call after the convention from former U.S. Rep. Barbara Kennelly, the Democrats' gubernatorial candidate that year, urging her to bow out, Bysiewicz went on to win the primary and later the general election. She held the seat for 12 years.
In 1992, when Bysiewicz was running for the state House of Representatives, former Middletown Mayor Anthony Marino was the odds-on favorite. She said no one thought she had a chance, but she knocked on the doors of 5,000 doors of registered Democrats - twice - and wound up winning the primary with 73 percent of the vote.
"What I've learned is primaries are about finding enough supporters to make this happen," Bysieiwicz told The Associated Press on Friday. She said she expects she'll need about 90,000 to 100,000 votes to defeat Murphy, depending on turnout.
East Granby First Selectman Jim Hayden, a delegate at Saturday's convention, said he received calls urging him to switch his support to Murphy, but he planned to stick with Bysiewicz. He said he has known Bysiewicz for a long time and credits her with appearing at his town to honor World War II and Korean war veterans, as well as for other events. He called her dynamic and said a primary will give the state's Democrats an opportunity to learn more about where the candidates stand on the issues.
"That's not always a bad thing," he said.
Murphy ultimately won 1,378 of the 1,823 delegates on Saturday. Bysieiwicz won 444 votes while East Hartford political newcomer Matthew Oakes won one vote.
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