Two byelections are under way in eastern Ontario to fill vacancies created at Queen's Park.

Voters are going to the polls, which are open from 9 a.m. to 9 p.m. on Thursday, to elect a new MPP in Leeds-Grenville and one in Ottawa West-Nepean.

The writs were dropped after former Liberal cabinet minister Jim Watson vacated his suburban Ottawa seat to run for mayor and veteran Progressive Conservative Bob Runciman stepped down in Leeds-Grenville after 29 years to take a Senate appointment.

The byelections are not expected to change much at the provincial legislature, some experts say.

Bryan Evans, a politics professor at Ryerson University in Toronto, said he'd be "shocked" if the rural riding of Leeds-Grenville switches parties.

He also said the Liberals will likely hang on to the suburban riding of Ottawa West-Nepean, given the party's star candidate Bob Chiarelli is a former Ottawa mayor who'd previously held the riding for 10 years.

Chiarelli is widely expected to be on the fast-track to cabinet if he reclaims the Ottawa seat he relinquished in 1997.

Former Brockville mayor Steve Clark hopes to hold on to the Leeds-Grenville seat for the Conservatives.

Clark will face off against Liberal Stephen Mazurek, New Democrat Steve Armstrong and the Green Party's Neil Kudrinko in Leeds-Grenville.

In Ottawa West-Nepean, Chiarelli is competing against Beth Graham, a former aide to both federal Health Minister Leona Aglukkaq and provincial Tory Lisa McLeod. School trustee Pam FitzGerald is representing the New Democrats and Mark MacKenzie is on the ballot for the Green Party.

With files from The Canadian Press