U.S. Rep. Allyson Schwartz, once the frontrunner for the Democratic nomination for governor, has not advertised on TV yet, but her campaign argued Wednesday in an widely circulated state-of-the-race memo that she is well positioned to win the May 20 primary despite that silence.

"We have over $5 million on hand to spend communicating with voters across Pennsylvania about Allyson's experience and leadership," writes Corey Dukes, campaign manager for Schwartz. "We have a deep base of support in the Philadelphia media market, which will only grow as voters hear our message. And, we have tremendous growth opportunities in every region of the Commonwealth."

Some Schwartz supporters have been anxious about the campaign's delay in going up on the air. Dukes said it was a strategic decision to advertise "when primary voters are actually making decisions about whom to support."

York millionaire Tom Wolf, who has given $10 million to his campaign, began advertising at the end of January and was little challenged in air supremacy for better than 50 days – though Katie McGinty paced him in some of the state's smaller markets.

State Treasurer Rob McCord went on the air Mar. 21, spending about $1.8 million on two weeks' of statewide TV time. He's spending about $600,000 over the next week, according to rival campaigns tracking ads. (McCord, a former venture capitalist, contributed or loaned $1.7 million of his own cash to the campaign.)

The Schwartz campaign cited three recent primary elections in which a candidate overtook a self-funder in the last days to win the Democratic nomination. In the 2007 Philadelphia mayor's race, for example, Michael A. Nutter (now mayor) beat businessman Tom Knox, who was sitting on a large lead.

In the Connecticut primary for governor in 2010, wealthy activist Ned Lamont took an early lead, but lost momentum once Stamford Mayor Dan Malloy went on the air with his record of experience; he cruised on primary day and is now governor in the Nutmeg State. Finally, the California Democratic primary for governor in 2006 was won by the state treasurer despite a wealthy candidate who spent $35 million.

Schwartz's campaign is betting that her experience in Congress and the state Senate will carry her, along with what it says is a deeply rooted voter-turnout operation.