The Progressive Conservatives have been spending a boatload of money on Facebook advertising in recent days, according to data released by Meta, Facebook's parent company.

For most of the campaign, the Liberals were significantly outspending their political rivals. Between April 15 and May 15, the Ontario Liberal Party, and its leader, Steven Del Duca, spent $516,000 on Facebook ads, or more than $17,000 per day.

READ MORE: Ontario Liberals betting heavily on Facebook ads

Meta separates the ads purchased by the party's page, and Del Duca's personal page.

READ MORE: Liberals peppering Del Duca’s riding with Facebook ads

The NDP and ruling Progressive Conservatives spent just over $100,000 each in the same period.

Over the long weekend, however, the PC Facebook ad machine began picking up steam. On May 16, the PCs spent just under $22,000 on Facebook advertising to the Liberals' $38,000. By May 20, the PCs were the top spenders. On May 20, the party spent $37,894, while the Liberals spent $31,013. On May 21 and 22, the PCs spent just over $42,000 and $49,000, respectively.

The Liberals, on the other hand, spent just over $36,000 and $42,000, respectively.

The NDP and Green Party have both spent comparatively little.

Overall, the NDP spent $104,000 between April 22 and May 22. From April 15 to May 22, the most recent data available, the party has spent an average of $4,139 on Facebook ads per day.

The Green Party spent just over $22,000 between April 22 and May 22. From April 15 to May 22, the party has spent an average of $1,324 on Facebook ads per day.

Other than Del Duca, no leader has spent any money on Facebook ads promoting them, personally.

The Liberals have 291 distinct ads in Meta's ad library. The PCs have 261, the NDP 327, and the Greens 35.

The PC ad buys appear to be working. Some of the PCs' most-watched Facebook ads have come over the last week, the data shows.

Since Meta started tracking ads a few years ago, the PCs have had 14 ads viewed between 900,000 and 1,000,000 times. Eight of those ads have come during the election campaign, with five in the past week.

Of the eight high-profile ads that've run during the campaign, three promote Ford and the PC platform, three attack Horwath and two go after Del Duca.

The anti-NDP ads cast them as the party of "no," but make no mention of Horwath herself. The anti-Liberal ads attack Del Duca directly. One tries to link him to former premier Kathleen Wynne, while the other says Del Duca had time in cabinet to "make choices," and it's time for voters to make theirs.

Meta's data is periodically updated and only goes up to May 22.

PCs starting to go hard on Facebook advertising

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