WASHINGTON – Labor Day week ought to start clarifying the partisan battle to control the Senate. But if anything, the picture just got muddier and the map bigger.

An afterthought all year, conservative Kansas is suddenly abuzz.

An independent candidate drove the Democrat from the race and positioned himself to consolidate discontent with three-term Republican Sen. Pat Roberts.

Washington-based GOP strategists are rushing to help Roberts, who is accused of sleepwalking through the race in the deeply Republican state.

If Kansas brought welcome news to Democrats, Alaska did not.

First-term Sen. Mark Begich initially was seen as running a smart campaign with excellent TV ads. But he endured withering criticism for a new type of ad, which he clumsily scrambled to remove from the airwaves.

The ad alluded to a sensational Alaska crime and accused the Republican nominee, Dan Sullivan, of being soft on criminals.

Sullivan was state attorney general at the time, but he had nothing to do with the prison sentence in question.

Critics denounced the ad, the crime victims’ relatives demanded its removal and Begich’s image suddenly went from savvy campaigner to truth-shaving attacker.

Democrats acknowledge that it hurt Begich, who’s running in a state that President Barack Obama lost by double digits in 2008 and 2012.

“But it hasn’t shifted the dynamic that Dan Sullivan is still going to be held accountable for his record,” which includes appointments to two state posts and being born outside Alaska, unlike Begich, said Democratic strategist Ty Matsdorf.

For all the noise in Alaska and Kansas, the overall Senate campaign landscape is as tight and unpredictable as before, strategists of both parties say.

“It’s within the margin of error almost everywhere,” said Republican consultant Mike McKenna, who has conducted recent surveys in several pivotal states.

In terms of gaining new seats, he said, “Republicans can go plus three, or plus 10. It’s too close to call.”

Nearly all candidates are struggling, McKenna said.

“The Republican brand has been in trouble a long time,” he said, thanks to a government shutdown and other steps that raised questions about Republicans’ ability to govern.

Yet Obama is damaging the “Democratic brand,” McKenna said, by being indecisive on problems such as the racial tension in Ferguson, Missouri, and Islamic extremists’ in Syria.

Republicans need six net seats to gain the Senate majority. They are heavily favored to win three where Democratic senators are retiring: West Virginia, South Dakota and Montana.

The most promising targets elsewhere are the four Democrats seeking re-election in states Obama lost, mostly by big margins: Arkansas, Louisiana, Alaska and North Carolina.

The two parties and outside groups are pouring millions of dollars into these states, mostly for TV ads.

The ads’ effectiveness is questionable, however, as the North Carolina race between Democratic Sen. Kay Hagan and GOP nominee Thom Tillis illustrates.

No state has seen more political TV ads this cycle, numbering 35,500 so far according to the Center for Responsive Politics.

5 ways GOP can get majority in Senate

Republicans need six new seats to control the Senate. Strategies to get there include:

Win the three easy ones – Republicans are heavily favored to replace retiring Democratic senators in West Virginia, South Dakota and Montana, states that President Barack Obama lost by 13 percentage points or more.

Go after Democratic senators in four states Obama lost – These incumbents are trying to hold on in Arkansas, Louisiana and Alaska, which Obama lost badly, and in North Carolina, which he lost narrowly in 2012. Two of these senators – Mary Landrieu of Louisiana and Mark Pryor of Arkansas – are battle-tested winners of multiple campaigns. The other two are first-termers.

Don’t lose any GOP-held seats – Democrats are making credible bids to win Georgia’s open seat and oust five-term Sen. Mitch McConnell of Kentucky, the Republicans’ Senate leader. An upstart independent has rattled Sen. Pat Roberts, R-Kansas. All three states went firmly against Obama, and Democratic victories would be upsets.

Pick up an open seat in a Democratic-leaning state – Democratic senators are retiring in Iowa and Michigan, which Obama carried twice. Republicans are making credible bids, especially in Iowa, where the Democratic nominee has had some stumbles.

Knock off a Democratic senator in a state Obama won – This should be the Republicans’ toughest task, but GOP Rep. Cory Gardner is running hard against Sen. Mark Udall, D-Colorado. A longer shot for Republicans is Scott Brown’s bid to topple Sen. Jeanne Shaheen, D-N.H.