With the Democratic U.S. Senate primary now less than three months away, the campaigns for Jeff Merkley and Steve Novick are increasingly engaging in a war of words.

The Merkley campaign has in recent days honed in on what it says is Novick’s broader pattern of hostility to the Democratic Party. The rhetoric from the Merkley side, observers say, marks a change in approach from just a few months ago when, it seemed, the campaign was determined to ignore Novick’s candidacy.

Jennifer Duffy, who monitors Senate races for the nonpartisan Cook Political Report, said the Merkley forces at first took the approach that Novick was not viable – and not worth engaging.

“What they missed is that in a Democratic primary (Novick) has experience and positions on issues that make him viable,” said Duffy.

At the heart of the Merkley offensive is the charge that Novick is not supportive of Democrats.

“Steve Novick is a guy who has run a campaign of attacking other Democrats,” said Merkley spokesman Matt Canter.

Canter later added:

"It really makes you wonder whether Steve Novick cares if Gordon Smith is reelected."

For evidence, the Merkley team points to Novick’s 1996 support for Green Party presidential candidate Ralph Nader and to a Feb. 5 Willamette Week article in which Novick spoke about Democratic presidential candidates Hillary Clinton and Barack Obama.

"I go back and forth,” the paper quotes Novick as saying. “I suspect I'll be disappointed with either one of them..."

The Novick campaign, meanwhile, is pushing back.

"Actually, this is sort of sad. After months of Jeff Merkley saying he was not going to mention Steve Novick and was focused on the general election, we've seen a stream of attacks from his campaign in recent weeks,” said Novick campaign manager Jake Weigler.

Weigler also explained Novick’s previous support for Nader, writing in an email:

“After it was clear Bill Clinton was going to win in a cakewalk in 1996, Steve cast a protest vote to register his frustration with Clinton's support for NAFTA and the Defense of Marriage Act. In 2000, he publicly urged Nader supporters to get behind Gore.”

The Merkley campaign, for its part, says it is not attempting to sharpen contrasts with its primary rival but rather responding to attacks from Novick on issues like deficit spending, Iraq, and social security.

"My opponent in the primary, by contrast, says he plans to continue to tax income from work at a higher rate than income from wealth, and to exempt most of the incomes of the wealthy from the Social Security tax,” Novick said in a February release. “Like Bush and Smith, although to a lesser extent, Speaker Merkley is dodging the deficits."

“Steve has attacked Jeff since day one,” said Canter.

Nathan Gonzales, who analyzes senate campaigns for the nonpartisan Rothenberg Political Report, said the Democratic primary was “certainly a more competitive primary than what we saw six months ago,” and that the Merkley side was engaging Novick because it saw him increasingly as a threat.

“Most often, candidates do not engage their opponents unless they think there is a threat,” said Gonzales.

At this point in the race several questions remain unanswered.

One is if the intensified Democratic engagement will hurt Democratic unity and affect the general election race with Republican Gordon Smith in November.

What also remains unclear is, with two months away from the election, if voters are paying attention to the back and forth.

Campaign observers stress that Merkley still maintains the advantages of an establishment frontrunner, including a war chest that outraised Novick by over $300,000 in the fourth quarter.

Merkley is still in front for the nomination, Duffy says, “but he will have to work for it.”

The Novick side, however, says Merkley’s attacks are a sign its campaign is catching on.

Sitting on the sidelines are Republicans, who say they are ready for battle in November no matter who emerges.

“Regardless of who comes out of that primary, we believe Senator Smith is well-positioned for reelection,” said National Republican Senatorial Committee spokesman John Randall.