They were plenty of voices in the party saying he should call an election, and he should have (even without hindsight). But in any case in the 2005 election the Tories actually campaigned on "vote Blair get Brown" so it wasn't a total surprise for the electorate.We vote for a local constituency MP and party, no a PM or president.
Didn’t hear a peep from a labour supporter calling for an election when Brown took over.
The game changer is the five year Parliaments, whereby a new PM cannot simply call an election. Big question now is whether enough Tory MPs would jump ship if Boris became PM and went for No Deal... enough to lose a no confidence vote?