Top sources in McCainworld, though, say this morning that no final decision has been made.
There are mixed signals at this point as to whether Romney has emerged as the favorite.
That seems to be the "body language" from the small group of aides who McCain is consulting on the decision, a GOP source says.
And that interpretation was reinforced when word spread among Romney loyalists last night that the vice presidential rollout tour included Michigan.
But Michigan is a battleground, and the tour also includes a stop in the swing state of Ohio a week from today.
Making matters more confusing, Politico has learned that McCain will visit suburban St. Louis for a major rally with Romney and his still-bitter primary nemesis Mike Huckabee on Sunday, Aug. 31, the day before the start of the GOP convention.
Top Missouri Republicans yesterday received the invitation for a rally featuring McCain and his two top primary challengers. They'll be joined by country star John Rich at a minor league baseball stadium in O'Fallon, Mo., about 35 miles west of St. Louis.
Missouri was hard-fought territory on Super Tuesday, with each of the three Republicans faring well. So the event would seem to represent a pre-convention unity rally in a swing state where each has a strong following. But Huckabee and Romney can hardly stand one another, and Huckabee has warned twice this month against selecting his once and perhaps future rival.
It would take a considerable act of pride-swallowing for Huckabee to stand before thousands of fans and watch as McCain touts Romney as his running mate.
But then it would take the same amount of magnamity for Romney to join such a rally the day before the convention if McCain were to tap somebody else as his veep choice and then laud that person in Missouri.