A new Nanos tracking poll shows a tight race across the country as support for the Conservatives falls to the lowest level in three and a half years.

The Nanos number:

32

percentage national support for the Conservatives - the lowest support in Nanos tracking since August 2009.

Source: Nanos national telephone survey of 1,000 Canadians 18 and older conducted Feb. 19 to 24, 2013. Accurate to +/-3.1 percentage points, 19 times out of 20.

The Nanos Research tracking poll shows the race tightening between all three parties across the country.

The Conservatives are still leading, sitting at 31.5 per cent nationally. Support for the Liberals is at 29.1 per cent, the NDP are sitting at 27.2 per cent, the Green Party is at 5.9 per cent and the Bloc Québécois is at 5.2 per cent.

The results are from a Nanos national random telephone survey of 1,000 Canadian aged 18 years and older, conducted between Feb. 19 and 24. The results are accurate to within 3.1 percentage points, 19 times out of 20.

Conservative support is at the lowest level in the Nanos tracking poll since August, 2009.

Nanos says the numbers are interesting because they not only show a close race nationally between the three main federal parties, but also reflect tight races in battleground provinces such as British Columbia and Ontario.

"Battlegrounds that will see additional seats, that will be critical in terms of the next federal election," Nanos said Wednesday on CBC News Network's Power & Politics.

The race is also tight in Atlantic Canada and Quebec, Nanos said.

"The Bloc still has a pulse [in Quebec], they continue to trail the New Democrats, but they are starting to trend up a bit," Nanos said.

The only region where there hasn't been much movement is the Prairies, where the Conservatives still have a hold on the majority of support.

Conservatives trending downward

A poll is a snapshot, but the real story is in the trend, Nanos said.

"[For] the Conservatives over the last number of months, since the last election, has been negative. It's been slowly eroding."

Nanos said the decline could be government fatigue, noting the Conservatives have been in government since 2006. Or "it could just be a slow erosion of support," he said.

"I don't think there's been any what you would say signature initiatives. The Conservatives have lowered the HST, they've done the stimulus, they've cut government. The prime minister has been very pro-active with international trade and he's focused on the energy economy, but there hasn't been a lot lately."

It could also have something to do with the opposition parties.

Support for the opposition parties, especially the Liberals, is starting to pick up. But with the focus on the Liberal leadership race, NDP support has started to slide a bit, Nanos said.

As well, "the Liberals and the New Democrats haven't really made mistakes. In the past, the Conservatives have benefited by out-smarting their political opponents, forcing them to make mistakes," Nanos said.

We haven't see that so far, Nanos said, and as a result it's a tighter race.

Canadians should also expect the polls to change over the next few months, as the Liberals choose a new leader and they settle on to the political stage, Nanos said.

Nik Nanos digs beneath the numbers with CBC Power & Politics host Evan Solomon to get to the political, economic and social forces that shape our lives. Recognized as one of Canada's top research experts, Nanos provides numbers-driven counsel to senior executives and major organizations. He leads the analyst team at Nanos, is a fellow of the Marketing Research and Intelligence Association, a research associate professor with SUNY (Buffalo) and a 2013 public policy scholar with the Woodrow Wilson International Center for Scholars in Washington, D.C.