TORONTO -- Ontario's New Democrats asked the provincial auditor Tuesday to probe advertising done by Metrolinx, accusing the provincial transit planning agency of helping to promote the Liberal government.

Metrolinx spent $237,000 on television ads during last Sunday's NFL conference championship games, money that would have been much better spent on providing public transit services, said New Democrat Cheri DiNovo.

"I was watching the NFL games with my husband and I personally was shocked to see Metrolinx ads," DiNovo told reporters.

"These are precious dollars, and to what end, to what purpose? Are they selling Liberal politics? If not, what is it that they're selling?"

The NDP wrote auditor general Bonnie Lysyk to ask for a formal review and value-for-money audit of the Metrolinx ads.

"At a time when the Liberals are suggesting that Ontario families need to pay hundreds of dollars in new taxes, tolls and fees for transit, they deserve to know why hundreds of thousands of dollars are being spent on advertising campaigns that appear to align with the interests of the Liberal Party," wrote DiNovo.

"I hope the auditor's office will ask tough questions about the goal of this campaign and whether Ontarians received value for their transit and transportation dollars."

Metrolinx said the three-week television commercial buy was for "many spots across many channels," not just the football playoff games, and aired only in the Toronto-Hamilton area.

"Metrolinx is a relatively young organization and we have heard over and over again that the public doesn't understand our role or often don't know who we are," said spokeswoman Anne Marie Aikins.

"There is also this notion that nothing is being done to build the transit we need, when in fact a lot is happening."

People want their transit money spent on transportation, not on glitzy ad campaigns, said DiNovo.

"It seems highly suspect that the premier of the province would one day come out and talk about how transit will not move ahead unless Liberals are elected, and the next day we've got Metrolinx talking about how wonderful transit projects are under the Liberals, during an NFL championship game," she said.

"We're saying the goal is politicking."

But speaking at an unrelated event in Waterloo Tuesday, Wynne defended the ads from Metrolinx.

"The advertising that Metrolinx is doing is about giving people information about what the organization does, what its role in public transit is, and that's information people need because we're in a period of major transit building at the moment," said Wynne.

"It's important that people understand the importance of building public transit."

Most Ontario government advertising is submitted to the auditor general for approval to make sure it isn't partisan, but ads from provincial agencies are not subject to the same pre-clearance process.