No way. Reagan would have made the communist label stick. And Reagan would have laughed at McPain, nicely, but he would have done him like he did Mondale.
True. Reagan would've managed the RINOs and moderates well, and within his 11th comandment, "Thou shalt not speak ill of a fellow Republican."
However, the "true conservatives" would've savaged him from within the party. They would've beaten him down for signing amnesty, for selling arms to terrorists in Iran, for cutting-and-running from Lebanon, for nominating an NWO RINO like GHW Bush.
No way even a young Reagan beats Obama in Nov 2008 with the condition of the world and the conservatives as it was.