In 2010, McKenna ran for the municipal election in Burlington's ward 1 but lost to incumbent Councillor Rick Craven.

[5] She supported Patrick Brown in his successful bid to become leader of the Progressive Conservative Party of Ontario.

[6] In December 2016, McKenna won the Progressive Conservative Party of Ontario nomination by a margin of 41 votes for Burlington, her old riding.

[7] In the 2018 Progressive Conservative Party of Ontario leadership election, McKenna supported Caroline Mulroney's unsuccessful bid.

[8] Following her election defeat, Mckenna was appointed as a provincial representative by the PC Government to the Halton Police Services board in March 2023.