A more realistic way of gauging their strength will be to ask about the size of their majority. And it is likely to be minuscule. If it reaches double digits, Republicans will have done very well. More likely, John Boehner will be elected speaker by a handful of votes.
Moreover, it appears increasingly likely that Republicans will have to share control of Congress with a Democratic Senate. For the first time in eight decades, a shift in control of the House may not be accompanied by a similar shift in the Senate. The mandate that is being given the GOP is of the most provisional sort.
What this means to me is that the voters are withholding any real verdict on their party preference. The polling says that the ratings they give the parties individually have rarely been weaker. Large majorities of Republicans express doubts about the GOP. And large majorities of Democrats about their own party.