Incumbent Sen. Christine Kaufmann took a major step toward returning to the Montana Senate on Tuesday, defeating fellow Democrat Rep. Hal Jacobson in a district that's traditionally a Democratic stronghold in the state.

As of 11:30 p.m., Kaufmann, 56, had collected 55 percent of the vote, outpolling Jacobson 2,528 to 2,070 in Senate District 41, which includes much of central Helena along with the city's West Side and a swath of the southwestern corner of Lewis and Clark County.

"This was by far the hardest campaign I've ever run," Kaufmann said. "But I had lots of volunteers and tremendous support, and I needed all of that to defeat a quality opponent like Hal Jacobson."

Kaufmann and Jacobson have worked alongside each other for years, which Kaufmann said made the race especially difficult.

"Not only is it hard to run against someone who you've worked with and who you respect, but you have so many acquaintances and friends who are torn," she said. "It's tough on people to have to make those kinds of choices."

Jacobson said he wouldn't have done anything differently.

"I ran a most honorable campaign, like I always do. I did what I thought was right," Jacobson said. "I've been out-spent by at least three to one, plus the big thing is the PAC money that has been spent on Christine."

Kaufmann goes on to face Republican Robert Leach, unopposed in Tuesday's GOP primary, in the Nov. 4 General Election.

She soundly defeated Leach for a seat in the House of Representatives in 2004.

Kaufmann, executive director of the Montana Human Rights Network, ran on the strength of a career in advocacy work, touting her efforts on behalf of women and the environment throughout her working life in addition to the Legislature.

She served three terms in the House and was elected to a fourth in 2006, but before the '07 session she was appointed to the Senate seat vacated when Ken Toole was elected to the Public Service Commission.

Jacobson, 57, served four terms in the House representing the West Side of Helena.

In this campaign he stressed his ability to steer legislation through the process, and his willingness to cede the spotlight in order to get things done.