SOMEWHERE BETWEEN NEWARK AND DAYTON, OHIO, ABOARD THE ROMNEY "EVERY TOWN COUNTS" BUS - Among Washington, D.C., political insiders, Ohio Sen. Rob Portman is considered one of the most likely to be picked as Mitt Romney's running mate.

But, here in northeastern and central Ohio, even among the GOP faithful, his name draws more question marks than exclamation points.

Theresa, Tami and Tim Clark, siblings from Lancaster Ohio, stood in a sunny town square in Newark waiting for Romney to arrive and address the assembled crowd. All three were supportive of Romney, though Tim said he drove the 26 miles to see what Romney has to say "straight on" instead of relying on what he gets from TV ads and news reports.

When asked what they thought about Portman as a potential VP pick, Theresa admitted she didn't know much about him.

"What state is he from?" she asked.

Her brother Tim, replied that "he's a senator or a representative" from Ohio.

But, while she knew nothing of Portman, Theresa had heard of one potential VP candidate that intrigued her.

"I like [Florida Sen. Marco] Rubio," she said.

Cathy Ford and Cynthia Johnson were also on hand for Romney's Newark speech. Both are strong Romney supporters. Neither knew much about Portman. If Romney picked Portman, said Cathy, "it wouldn't influence their vote." Even so, they said that they "trust Romney will make the right choice," in his running mate.

Portman represented Cincinnati from 1993 until 2005 when he was picked U.S. Trade Representative. He was elected to the Senate in 2010. A poll taken by Quinnipiac University in May found that 59 percent of Ohio voters hadn't heard enough about the freshman senator to give an opinion on him.

Perhaps the most telling example of Portman's anonymity came from an event earlier this morning in Brunswick, Ohio. Romney, his wife Ann, and two of their sons were doling out hotcakes for rain-soaked supporters. Portman stood close by cooking up some of the pancakes.

Standing with a crowd of Romney supporters, I overheard a man asked if the "gray haired" guy flipping the pancakes was Romney's son Tagg.

No, replied another person in the crowd, "that's Senator Portman."

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