Sen. Chris Murphy is advancing to the November election after sailing through the primaries without facing a challenger from his Democratic Party.
The first-term senator from Connecticut will face the winner of a two-man Republican primary featuring small-business owner Matthew Corey and Apple computer executive Dominic Rapini.
Polls in the state closed at 8 p.m. Minnesota, Vermont and Wisconsin are also holding primaries Tuesday.
Murphy's campaign has raised about $13.5 million, an amount that far exceeds the fundraising of each of his GOP rivals.
Murphy was first elected in 2012 and became a prominent advocate for gun control following the shooting massacre that year at Sandy Hook Elementary School in Newtown that killed 20 first-graders and six educators. He has gained a higher profile lately through his outspoken criticism of the policies of President Donald Trump.
Corey, a small business owner, has won the Republican nomination for U.S. Senate in Connecticut and will face an uphill battle against Sen. Murphy.
In Tuesday's primary the Manchester Republican defeated Dominic Rapini, a national accounts manager for Apple computers.
Corey is a U.S. Navy veteran and owner of a Hartford pub and a window-washing business. He earlier unsuccessfully challenged Democratic U.S. Rep. John Larson.
Corey has called for more investment in small businesses in low-income communities. He's also supportive of apprenticeship programs, corporate tax reform and a tax credit for home school parents.
As of July 25, records show Corey had raised about $31,000 in campaign funds compared with nearly $13.5 million for Murphy.
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