BILLINGS — Democrats John Driscoll and John Lewis have spent much of their lives in politics, yet their paths to the June primary for Montana’s sole U.S. House seat couldn’t be more different.

Driscoll, 67, is both an old political hand and an iconoclast. The one-time state House speaker is forgoing primary campaign donations and instead hoping to sway voters through personal connections built over a political career that dates to the early 1970s.

He said he would take money in the general election if nominated but first wants to demonstrate he’s not beholden to donors and would be able to work across party lines.

Lewis, 36, is simultaneously a new face and a political insider. He spent 11 years working for former U.S. Sen. Max Baucus before launching his first bid for elected office last fall with strong backing from the Democratic establishment.

Topping Lewis’ list of priorities are education, job training and building up Montana’s infrastructure, including more access to broadband Internet and transportation improvements.

The House seat opened up when first-term Republican Rep. Steve Daines decided to run for the Senate post vacated by Baucus. Five candidates are vying for the Republican nomination.

Conventional wisdom would have Lewis cruising to an easy victory — he’s already spent roughly 50 times more money than his opponent ahead of the June 3 primary. He’s been endorsed by the state Democratic Party, unions and other groups eager to reclaim a seat Democrats last won in 1994.

But Driscoll has defied the odds-makers before. In 2008, the retired U.S. Army colonel and former public service commissioner won the U.S. House Democratic primary by edging out a Helena lawyer who had support from party leaders, and did so without taking a dime in contributions.

The question is whether Driscoll can deliver a repeat. His dismal performance in the 2008 general election remains a sore spot for some Democrats. He lost by a 2-to-1 margin and at one point suggested he would vote for his Republican opponent.

“It’s hard enough to turn that trick once, and now he’s trying to turn it against someone with the full backing of the party and plenty of money who comes across as totally credible and viable,” said University of Montana political analyst Robert Saldin.

For his part, Lewis could find it hard to escape the shadow of Baucus, his former boss.

Baucus served six terms before stepping down to become the U.S. ambassador to China. His popularity had dropped among some voters because of his central role in crafting the bill that became the nation’s health care overhaul. Republicans have seized on the Baucus-Lewis connection, including with a bogus “johnlewis4congress” website that urges Lewis to “retire from Washington.”

Lewis said he’s proud of the work he did for Baucus but is running as his own man.

“I earned that support,” he said of his backing from party leaders. “Whether it’s somebody in the local central (Democratic) committee or a union, they want to meet you, shake your hand, size you up. You’ve got to go and earn that support.”

Lewis was born in Billings and went to high school in Missoula. He received a bachelor’s degree in political science from Western Washington University before going to work for Baucus in 2002. He’s lives in Helena and is married with two children, ages 6 and 8.

If elected, he said he would adopt a simple strategy for his dealings in Congress: “Cooperation, not compromise.” He learned the phrase from his mother, a professional facilitator.

He raised nearly $700,000 by the end of April, including $189,000 from political committees.

Lewis said there’s too much money in politics, but he needs to counter the negative image of him promoted by Republicans.

“It’s going to take too much to get this done, but that’s the way it’s done,” he said.

Driscoll, by contrast, has pledged to spend no more than $5,000 on the primary. He had spent about $4,234 as of Tuesday and plans to curtail his travels if he exceeds the self-imposed limit.

Born in California, Driscoll comes from a longtime Butte family and now lives with his wife in Helena. They have four grown children.

Driscoll originally considered running this fall as a Republican U.S. Senate candidate to offer a moderate alternative to Daines. He said he changed his mind because he felt more comfortable running as a Democrat and recalled some advice he once received from former U.S. Sen. Lee Metcalf, who said it was easier to get things done in the House.

Like Lewis, Driscoll opposes a reduction to Medicare suggested by some Republicans.

But Driscoll says Democrats went too far in their opposition to the GOP budget plan from Rep. Paul Ryan of Wisconsin, which would cut more than $5 trillion over the coming decade. Despite disagreeing with Ryan’s politics, Driscoll said his proposals provide a framework for spending decisions.

“You start to say anything that has Ryan associated with it and you feel like you’re in a room with Barney Fife unloading his machine gun, everybody shooting at each other,” he said. “At least it gives you a place to start. Right now, it’s like they don’t want to make things work.”