A new poll suggests the federal Liberals have recovered from their post-India slump, regaining a commanding lead over the Conservatives.

It also indicates that Prime Minister Justin Trudeau's base of support has gotten softer — a sign that his ill-fated trip to the subcontinent might have had a longer-term impact.

The new survey by Nanos Research puts the Liberals at 41 per cent support, followed by the Conservatives at 29 per cent and the New Democrats at 16 per cent. The Greens and Bloc Québécois posted eight and four per cent support, respectively.

On the face of it, that result represents a broad shift from where the polls placed the Liberals in the weeks following Trudeau's visit to India — a diplomatic mission plagued by widely-mocked wardrobe choices and the unfortunate decision to invite a man convicted of attempted murder to some official events.

In the first weeks of March, Abacus Data pegged the Liberal lead over the Conservatives at just three points. Léger put the two parties in a tie. Twice, Ipsos/Global News put the Conservatives ahead — its latest survey put the gap at seven points — and the Angus Reid Institute has awarded Andrew Scheer's party a 10-point edge.

But throughout this period, Nanos never put the Conservatives in front. The pollster's four-week rolling surveys of 1,000 Canadians (every week another 250 respondents are added to the sample as the 250 respondents polled four weeks earlier are dropped) have given the Liberals a lead in every week's release since the 2015 federal election. The closest the margin has been was 1.1 points, in the four-week poll ending on Mar. 16.

Methodology could explain the variation. Abacus, Léger, Ipsos and the Angus Reid Institute conduct their polls online, while Nanos polls over the phone.

This poll also could be an indication that the impact of the India trip on the Liberals' support was a short, sharp shock — something picked up by polling in the week or two running up to Mar. 16 but swamped by the Liberals' strong pre-India polling in the four-week average.

Perhaps the Liberals have regained the support they lost in early March, but one survey won't be enough to tell us. It will take subsequent polling from other firms to get a clearer picture.

In the meantime, the CBC Poll Tracker splits the difference. It finds the Liberals and Conservatives in a tie, though the Liberals are in a better position to win more seats.

But what the Nanos poll does show is that the Liberals shouldn't be popping champagne corks just yet. Despite the wide lead on voting intentions, a number of other metrics have gotten worse for the governing party.

Liberal support looks softer now

The last time the Liberals were at 41 per cent in Nanos's polling was in the survey ending on Jan. 5, which put the party 10 points ahead of the Conservatives. Other surveys in the field at around that time were showing similar numbers.

But while the Liberals may be doing just as well among decided voters as they were a little more than three months ago, their wider universe of supporters has gotten smaller.

The gap in polling support between Prime Minister Trudeau and Conservative Leader Andrew Scheer suggests the Liberals' recent polling slide was self-inflicted. (Justin Tang/Canadian Press)

On the question of who Canadians think would make the best prime minister, Trudeau now scores 39 per cent. That's down six points from his score in January. That still puts him 16 points ahead of Scheer (another indication that the Liberals' recent woes are largely self-inflicted, rather than due to a surge of popularity for the Conservative leader) but it means that Trudeau is now scoring lower than the Liberal party itself does among decided voters.

According to the latest survey, Nanos finds that 51 per cent of Canadians would consider voting Liberal, compared to 44 per cent for the Conservatives and 36 per cent for the NDP. But that's also down six points for the Liberals from Jan. 5.

And while 55 per cent of Canadians surveyed recently said that Trudeau has the "qualities of a good leader" — better than Scheer's 40 per cent and NDP Leader Jagmeet Singh's 34 per cent — that number is down a sizeable 11 points from Jan. 5.

More polling will be required before a Liberal rebound in voting intentions can be confirmed or debunked. But the results on some of the other questions asked every week by Nanos suggest that the Liberal party and the prime minister himself have taken a hit — which is in line with what other polls have found.

That could signal the Liberals' support has gotten softer, making them more vulnerable in the future.