He distanced himself even further from the GOP establishment Friday with his vice-presidential pick. Alaska Governor Sarah Palin is a young, outside-the-beltway choice with a record of taking on entrenched interests.
Even so, many Republicans are bracing for a period of exile. A debate is already under way over its future, with conservative visionaries from former House Speaker Newt Gingrich on down arguing about what it will take for the Grand Old Party, its best ideas now spent, to stage a comeback.
"If the Republican Party is not thoroughly repudiated in this coming election it will only be to the extent that John McCain and some of the other Republican candidates have managed to distance themselves from what's happened over the last eight years," he says.
Their gathering in this Midwestern city offers a fresh chance for Republicans to make their case to a skeptical nation.
The GOP convention begins just four days after Barack Obama accepted the Democratic nomination at a Denver football stadium thronged by some 84,000 cheering supporters, some of whom waited in a line six miles long to hear his speech.