Ramesh, you make good points and none of this is provable. The reasons I think Cruz would have been even stronger without Trump are that Cruz, not Trump, would presumably be winning Republicans who are angry at Washington and want an outsider, and those have been big swathes of the primary electorate; Cruz would be the hard-liner on immigration in the field; and he really would have won in the South, which was supposed to be his regional base going into this thing.
Ted Cruz & Donald Trump -- Contested Convention↧