By Rick Sallinger

DENVER (CBS4) – It was a compelling story and voters responded. Tom Sullivan’s son, Alex, was among the dozen killed in the July 2012 Aurora theater shooting.

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Alex Sullivan (credit: CBS)

Now, Sullivan has been elected to the state House of Representatives.

CBS4 first met Tom Sullivan on the worst day of his life as he desperately held up a photo as he was searching for his son.

“Alex Sullivan… I’m his dad.”

Tom Sullivan in 2012 (credit: CBS)

His son had gone to see the new Batman movie with friends for his 27th birthday.

“I just think that’s what everyone would do. You’re trying to find him and maybe someone has seen him,” he recalled.

Alex and 11 others were murdered in the theater that night when a gunman opened fire.

Since then, Tom has been outspoken about gun violence testifying at legislative committees to some, he said, didn’t want to listen.

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(credit: CBS)

“What we will do is do what I did and build a coalition and we will run you out of your office,” he promised.

And so he decided to run as a Democrat in the state House of Representatives in the heavily-Republican district of Arapahoe County. He defeated the incumbent Cole Wist. It was part of Colorado’s blue victory Tuesday night.

“We’re all in this together. Everyone was doing their part, and that’s what teams do,” Sullivan said.

He will be taking office in January at the Capitol and already wants to revive the “Red Flag Bill” for those deemed a significant risk to themselves and others.

(credit: CBS)

“To be able to temporarily remove their firearms from them and evaluate in another six months,” he said of the bill. He will also pursue victim rights legislation.

(Pic rick and sullivan)

“What would Alex say about what you have accomplished?” CBS4’s Rick Sallinger asked.

“‘Way to go dad!’”

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CBS4’s Rick Sallinger is a Peabody award winning reporter who has been with the station more than two decades doing hard news and investigative reporting. Follow him on Twitter @ricksallinger.