If McCain leaves a hole, can Giuliani fill it?

Surely all the Republican candidates will try to capitalize on the misfortunes of Senator John McCain's presidential campaign, which some pundits argue is on life support after two underwhelming fund-raising quarters. But Rudy Giuliani seems to be aggressively filling the void, or trying to, by announcing a slew of hires, endorsements, and field organization improvements.

In the last few days, Giuliani's campaign has unveiled teams of supporters in Georgia, Iowa, and California; he's announced his Justice Advisory Committee, led by Ted Olson, a former US solicitor general; and he's opened offices in Lexington County and Charleston County, SC.

One interesting aspect of all this is that Giuliani is making a big show of his efforts to woo some pretty conservative parts of the country, which gets to the heart of the question surrounding his candidacy: Can a pro-choice, pro-gay rights guy from Brooklyn win a Republican primary? Look for reports from Giuliani's visit today to conservative northwest Iowa.

Mitt Romney, meanwhile, returns to South Carolina tomorrow for another "Ask Mitt Anything" event in Spartanburg and a barbecue in West Columbia. And Fred Thompson is reportedly hosting a fund-raiser on the Cape this Saturday.