HELENA -- It didn't take long for U.S. Sen. Conrad Burns to go on the offensive Tuesday night, once he knew his Democratic opponent this fall -- about 15 minutes.

Burns, fresh off his own Republican primary victory, took aim at Democrat Jon Tester, asking how the Democratic nominee would vote on constitutional amendments to ban gay marriage and ban burning of the American flag, and on abolishing the so-called "death tax," which is the federal income tax on inherited wealth over $2 million.

"These are all important issues and Montanans deserve to know how you'll vote," Burns said in a statement released 17 minutes after Tester was declared the winner of the Democratic primary.

Burns' campaign continued the thought Wednesday morning, calling Tester an "unabashed liberal" out of touch with Montana values and more suited to being a senator from New York or Massachusetts.

"What it comes down to is that Massachusetts doesn't deserve a third senator," said Burns campaign spokesman Jason Klindt. "We need someone who advocates for Montana values and has the seniority to deliver."

The aggressive approach from Burns confirms what most people already knew: This race will be a slugfest, from the opening gun to the finish line.

"The gloves are off already," said Craig Wilson, political scientist at Montana State University-Billings. "This is a 15-round, bare-knuckles political contest."

Burns, up for re-election to a fourth consecutive term, is considered one of the most vulnerable Republican incumbents in the country.

Political party officials in Washington, D.C., acknowledge it's a key race in the battle to control the U.S. Senate. Democrats, especially, say it's at the top of their list.

"I think it's safe to say that Jon Tester will have all the resources he needs to take on Conrad Burns and his big-money, special-interest campaign," said Karl Frisch, press secretary for the Democratic Senatorial Campaign Committee.

Burns has about $3 million in his campaign fund; Tester will start near ground zero, but can expect help from Democratic supporters across the country.

Burns also has committed to a pair of debates with Tester and is asking for more -- a tactic unheard of by an incumbent who thinks he's secure, said Larry Sabato, a political scientist and director of the Center for Politics at the University of Virginia in Charlottesville, Va.

"It's a recognition by Burns that his best chance of winning is to paint Tester as an out-of-the-mainstream liberal," Sabato said of the early offensive and request for debates. "That's probably his best shot. But he has his own baggage."

The "baggage" mentioned by Sabato is Burns' ties to disgraced lobbyist Jack Abramoff, whose associates and clients gave more campaign money to Burns than to any other member of Congress. Burns has returned the money and denied any undue influence by Abramoff.

Tester, a Big Sandy farmer and state senator, didn't waste time Wednesday playing the Abramoff card. Tester also took a shot at Burns for the latter's support of a bill last month that will raise taxes on college savings and eliminate a tax deduction for college tuition.

"Senator Burns hasn't leveled with Montanans about his associations with Jack Abramoff and he's lying about his record on taxes," Tester said. "Burns has shown he'll do or say anything to keep his job."

In an interview Wednesday, Tester said he's ready to talk about issues, too -- and not necessarily the issues broached by Burns.

"We need to talk about the issues that are important to this country," Tester said. "We've doubled the national debt in five years.

"The Republicans have been working for big multinational corporations instead of consumers. It's the same thing on medical care, on energy, on pharmaceutical drugs. They have a poor record in serving small businesses, family farms and ranchers, and working families."

Tester also said he'll gladly tell people his position on the issues brought up by Burns Tuesday night -- although Tester said those aren't issues he hears people talking about.

He said he opposes a U.S. constitutional amendment banning gay marriage. Montana already bans gay marriage, and the federal constitution doesn't need to be amended to discriminate against people, he said.

On flag-burning, Tester said there's not even a proposal on the table, but that he would oppose amending the U.S. Constitution to ban flag-burning: "I don't condone burning the flag, but I certainly don't want to amend the constitution taking away free speech."

On the estate tax, Tester said he thinks estates below $3 million should be exempt from federal taxation. Republicans are pushing to abolish the tax entirely.

The Burns campaign said it intends to run an issue-oriented campaign, and wants to talk about not only gay marriage and taxes, but also the war on terror, immigration and the role of government.

"We believe that (this campaign) is about a true conservative versus a true liberal," said Klindt. "This is going to be a great debate, from Jon Tester, who is unabashedly liberal, to Conrad Burns, who is a common-sense conservative."

On Wednesday, Republicans also tried to cast Tester as a pawn of Eastern Democrats, who would rush in to take over his campaign or dictate how to run it.

Tester said he's not going to let that happen.

"We ran this campaign in the primary and we weren't expected to win this doggone thing," he said. "And we still did it, and we did it by reaching out and talking to people, by developing a plan and sticking to it."

"This isn't Charles Schumer's campaign," he continued, referring to the New York senator who chairs the DSCC. "It's not Max Baucus' campaign. This is Jon Tester's campaign."