He is according to Angus Reid's latest poll, which says that Mulcair would lead the NDP to the best result in a general election today, and is the most well-thought-of among NDP members and the general public.
This being said, the results are so small between the question asked under Topp (which would result in 41-25-21), and the question asked under Mulcair (41-28-21), that it doesn't matter.
Except, that is, in Quebec, where it matters greatly. Under Thomas Mulcair, the NDP would grab 52% of the vote, leaving the other parties far behind. Under Topp, the NDP would drop to just 31% of the vote, with the Conservatives, Liberals, and BQ making some good gains.
To illustrate the difference, Mulcair's result would give the party 70 seats (!), with the other five going to the Conservatives, wiping out the Libs and Bloquistes. That's a gain of 11 on to the NDP's current number.
Under Topp, that would net the NDP 38 seats, 21 under what they currently have, the Conservatives would sit with 15, the Liberals with 12, and the Bloc with 10.
The only consolation for Topp is that Gary Doer would do worse in Quebec, as AR puts him at 27%. The again, Doer isn't even running.
The list of possible NDP candidates and if people feel they're a good choice is interesting, if farcical, including such names as the aforementioned Doer (who isn't running), Bill Blaikie, Ray Romanow (who endorsed Topp), Dawn Black (not running), Charlie Angus (also not running), Francoise Boivin (who also endorsed Topp) - and it goes on.
The names that matter are ranked here in order of their "popularity" among NDP supporters:
Thomas Mulcair - 35%
Brian Topp - 21%
Paul Dewar - 11%
Romeo Saganash - 10%
Pat Martin - 9%
Peter Julian - 6%
Nathan Cullen - 6%
Robert Chisholm - 5%
What does this mean? Well, Mulcair has two obvious advantages in the early race: he's clear and far the most popular "good choice," and he also probably has more name recognition that the others.
Topp, however, has established himself as the favourite competitor to Mulcair, at least so far. And given his lack of name recognition up until now (though, I figure he's more well known among Dippers), he's doing pretty well. The same goes for Saganash.
And of course, if Yvon Godin has his way, then Topp's the clear favourite to begin with....
Now, when will someone do this for the Liberals?