Incumbency in the 2015 Federal Election - does it make a Liberal win impossible?

I thought I would quickly look at the number of incumbents running for each party and how that might impact the election chances of the Liberals.  By this point it should be clear if an MP is running again or not and we should only see a few more drop out.  

        Current  Incumbents  Max Inc 
Party Incumbents Not Running Running 
CPC       163      23          140
NDP        95       7           88
LPC        35       5           30
Green       2       0            2
F+D         2       0            2
Bloc        2       1            1
Ind         7       2            5 

At the moment we have up to 268 possible incumbents running in the next election.   Historically incumbents have tended to do better than challengers, and yes there are huge exceptions to that.   But based on the past performance, it is a reasonable assumption that a large number of the incumbents will win again.   

If we look to the path the Conservatives took to get to power, it was by building on increases in the number of incumbents in each election from 2000 onward.   In no election did they have a dramatic break through but they just steadily built on the past.    

The Conservatives look like they will have somewhere between 130 and 140 incumbents running in 2015.   They should have a decent chance to hold 2/3s of those seats.   Of the 30 new ridings, about 20 of them are notionally Conservative based on transposing the 2008 and 2011 results.  What this says to me is that the Conservatives are likely comfortably on 100 to 110 seats as of now and need to find wins in 60 to 70 for another majority  

The NDP has 35 incumbents running in 2015 that were not elected from Quebec.  The big issue here is if they can hold onto to most of those seats or even increase the number.    I think the 17 incumbents in Ontario could be in question.   Of the nine in BC, I do not see any obvious ones that will lose. 

Remarkably, of the 59 Quebec MPs elected by the NDP in 2011, 55 of them are still with the party.   Of those, 53 seem to be running again for the NDP.   In 2011 only 7 of the 59 New Democrats elected in Quebec defeated Liberals.   In only 9 of those 59 did the Liberals come second.   Out of the 59 seats the NDP won, 45 of them had been previously held by the Bloc.    Is it realistic to expect the Liberals to win a lot of those seats?   How will the soft nationalists act in the election?  Unless the new party F+D gets a lot of traction, which the might, I think we will see a lot more New Democrats re-elected in Quebec than many pundits are expecting.   

Now comes the wildcard, the Liberals.   They are headed into the election with only at most 30 incumbents running again.   Even if they all win again and they rasily regain 2/3s of what they held in 2008 (based on the new boundaries) they are only at around 85 seats.  They still need to find another 20 to 25 seats to have any chance of being the largest party in the House of Commons but it would be a very evenly split house if they only got to  105 to 110 seats.   Realistically they need to find something like 50 more seats to have a moderately stable minority government.   That is a total of 105 new MPs for the Liberals.     It is a huge ask to get to that number.   It would the second highest increase in the number of seats for political party in a federal election.   This when polling has the Liberals either tied with the Conservatives or mildly ahead of them.

Biggest increases in seats since universal suffrage in Canada

1. +111 PCs 1984 - 22.0 pp lead over the Liberals
2. +97 PCs 1958 - 19.9 pp lead over the Liberals
3. +96 Liberals 1993 - 22.6 pp lead over Reform
4. +74 Liberals 1949 - 19.5 pp lead over the PCs
5. +83 Liberals 1935 - 14.8 pp lead over the PCs
6. +67 NDP 2011 - came second
7. +66 Conservatives 1926 - minority
8. +61 PCs 1957 - minority
9. +58 Progressives 1921 - came second
10. +51 Liberals 1962 - came second, minority PC govt
11. +51 Reform 1993 - came third
12. +45 Liberals 1988 - came second
13. +44 Bloc 1993 - came second

An increase of over 50 seats is rare in Canada and that would not be enough to allow the Liberals to be certain of being the official opposition.   To win enough seats there has be be a much stronger tide in favour of the Liberals.

In four of the 13 biggest increases in seats for parties the bulk of them came from Quebec.

The 1993 election stands out because three of the top 13 increases were in that election.   A total of 191 seats gained by three parties.  Nothing in for the 2015 election says to me that we are headed towards a 1993 type of election.  

Both the Conservatives and the NDP have to do remarkably badly to have a chance for a dramatic break through for the Liberals.  Much worse than polling seems to indicate.