Republicans won an open Senate seat in North Dakota in 2010 in a cakewalk. Given that result and the state’s conservative lean in a presidential year, when Sen. Kent Conrad (D) shocked the political world by announcing his plans to retire rather than seek reelection in 2012, it was considered something short of a given that the GOP would win the open seat contest in November.

But a series of polls in North Dakota in recent weeks — most of them from Democratic pollsters — show the race is neck-and-neck between former state Attorney General Heidi Heitkamp (D) and Rep. Rick Berg (R).

FILE - In this March 31, 2012 file photo, Senate candidate Rep. Rick Berg (R-N.D.) shakes hands with supporters in Bismarck, N.D. (AP Photo/Will Kincaid, File)

Two polls in the last week — from independent pollster Mason-Dixon and the North Dakota Democratic Party — show Heitkamp and Berg in a statistical dead heat. That tightness in the Senate race is in spite of the fact that same polling Republicans lead by double digits in both the presidential race and for Berg’s House seat.

So, what gives?

The polling right now seems to reflect Heitkamp’s statewide name ID and Berg’s early image problems. The fact that former Massachusetts governor Mitt Romney and the GOP’s newly minted House candidate, Kevin Cramer, both lead by double digits while Berg is tied shows that his campaign (and Republicans broadly) have some work to do when it comes to introducing — or re-introducing — Berg to the electorate.

(A Democratic Senatorial Campaign Committee poll conducted by pollster Mark Mellman in November showed Berg’s favorability rating at 42 percent with his approval at just 28 percent. The Mason-Dixon poll this week showed his favorable rating at 45 percent positive and 34 percent negative — slightly worse than Heitkamp.)

That Berg was in relatively poor position to start with is a bit surprising, given that he has been in Congress for such a short time and just came off a big victory.

Republicans ascribe it to the fact that he just finished a tough campaign against a 10-year incumbent Democrat, Earl Pomeroy, and had some lingering wounds from that bruising contest. In addition, it’s not exactly political gold to be a Member of Congress these days, and Berg’s campaign didn’t really ramp up for the general election as it dealt with a semi-serious primary against perennial candidate Duane Sand.

Republicans concede that the race is competitive right now — though they don’t concede that it’s tied — but emphasize that the months ahead will right the ship.

First, the GOP campaign against Heitkamp is really just beginning; most of the Republican messaging early on has been trying to prop up Berg.

Heitkamp’s campaign has done a good job in the meantime, Republicans acknowledge, of earning positive press. But with the presidential race next to her race on the ballot, it will be harder to distance herself from President Obama and his health care bill — both of which she has praised in the past — over the next four and a half months, they quickly argue.

This should not be under-estimated.

We saw in the Arizona special election on Tuesday how a candidate’s past statements can come back to bite them, and Republicans have video of Heitkamp praising the Obama health care law that they’re just starting to put serious dollars behind.

In fact, GOP-leaning outside groups American Crossroads and the American Future Fund are both up with Obamacare-focused ads today that feature video of Heitkamp.

Republicans also note that the same pollster that showed Heitkamp up 1 percent this week — St. Paul-based DFM research — showed her ahead by 5 percent in April — a suggestion that the trend may be in the GOP’s favor. In addition, while Heitkamp outperformed Obama by 17 percent in the last DFM poll, she now beats the president by only 9 percent.

That movement comes despite Democrats spending more on the airwaves in recent weeks. Heitkamp herself has launched more than $200,000 in ads, and she’s gotten some help from the Senate Majority super PAC and the Democratic Senatorial Campaign Committee. The only ads on the GOP side in recent weeks have been a small buy from the American Crossroads super PAC.

Given the GOP’s super PAC advantage nationally, that trend won’t likely continue.

In the end, it looks like we’re going to find out whether, as Tip O’Neill famously said, “all politics is local.”

North Dakota, after all, has sent lots of Democrats to Congress over the past few decades despite its conservative bent.

Most political analysts think the hyper-nationalized political environment will make it harder and harder for North Dakota Democrats to keep that up — particularly with both of their longtime incumbents, Conrad and former senator Byron Dorgan (D-N.D.), retired.

Heitkamp and her party don’t have an easy road in front of them, but they start the general election in surprisingly good shape.