Slowly but surely, the Conservatives have inched up in the polls, putting them in the best position they have held since this long campaign began to win the most seats on election night.

The CBC Poll Tracker shows the Conservatives holding a modest lead over the Liberals, with 32.5 per cent support against 30.4 per cent for the Liberals. The New Democrats sit in third with 27.2 per cent of the vote.

There have been some clear trends working in favour of the Conservatives. In the week of Sept. 13-17, the party was averaging 29 to 30 per cent in the Poll Tracker. That increased to between 30 and 31 per cent in the following week, and between 32 and 33 per cent this week.

The Liberals have held steady over that time, averaging 30 to 31 per cent over the last two weeks.

Instead, the New Democrats have felt the brunt of the Conservatives' increase. From an average of 31 to 32 per cent in the week of Sept. 13-17, the party fell to 29 to 30 per cent and now to between 27 and 28 per cent support.

This shift has largely been driven by dropping support levels in Quebec. The NDP currently stands at 33.9 per cent in Quebec, followed by the Liberals at 23.4 per cent, the Conservatives at 21 per cent, and the Bloc Québécois at 18.5 per cent. That represents a drop of nine to 11 points for the New Democrats since the week of Sept. 13-17, with the Conservatives and Bloc each gaining six to seven points. The Liberals are also down slightly in Quebec.

With the currently projected levels of support countrywide, the Conservatives would win between 115 and 159 seats, with the Liberals taking 79 to 122 seats and the NDP winning between 88 and 112 seats. The Bloc could take between zero and two seats, and the Greens one.

This gives the Tories a significant edge in the seat count, but still puts them below the 170 seats needed to form a majority government. This is a more important number for the Conservatives to reach than the other parties, considering that both Justin Trudeau and Tom Mulcair have said they would not support a minority Conservative government.

By contrast, winning a single seat more than the Conservatives could be enough for either the Liberals or NDP to take office, if they get the support of the other party.

Differing trends?

Two polls published on Monday suggest trend lines heading in different directions — at least for the Liberals and NDP:

A poll by Forum Research for the Toronto Star pegged Conservative support at 34 per cent, with the NDP at 28 per cent and the Liberals at 27 per cent. Compared with their previous survey conducted between Sept. 21 and 23, that represented an increase of three points for the Tories and a decrease of four points for the Liberals, with the NDP steady.

A poll by Nanos Research for CTV and the Globe and Mail put the Conservatives ahead with 32.8 per cent, followed by the Liberals at 31.7 per cent and the NDP at 26.1 per cent. Compared with where the numbers stood when Nanos was also in the field between Sept. 21 and 23, this represented a gain of 2.3 points for the Tories and a loss of 4.7 points for the NDP, with the Liberals steady.

The point of agreement, then, is on the increase in support for the Conservatives. This has also been reflected in other polls published throughout the week.

The question is whether the Liberals are keeping up with the Tories. Subsequent polls may shed light on whether the race remains close between the Liberals and Conservatives or whether Stephen Harper is on track for another victory Oct. 19.

What happens on Oct. 20 if it is not a majority victory, however, is another question altogether.

CBC's Poll Tracker aggregates all publicly released polls, weighing them by sample size, date and the polling firm's accuracy record. Upper and lower ranges are based on how polls have performed in other recent elections. The seat projection model makes individual projections for all ridings in the country, based on regional shifts in support since the 2011 election and taking into account other factors such as incumbency. The projections are subject to the margins of error of the opinion polls included in the model, as well as the unpredictable nature of politics at the riding level. The polls included in the model vary in size, date and method, and have not been individually verified by the CBC. You can read the full methodology here.

The questions asked in the polls mentioned in this article were as follows:

Nanos: "If a federal election were held today, could you please rank your top two current local voting preferences?"

Forum: "If a federal election were held today, which party are you most likely to vote for?"