Losses in key seats could cost Labor: poll

Labor is falling short of the support it needs in key marginal seats to secure a parliamentary majority in its own right, new polling shows.

New polling shows Labor is falling short of the support it needs in key marginal seats. (AAP)

Despite being in front in nationwide polling Labor is falling short of the support it needs in key marginal seats to secure a parliamentary majority in its own right, a survey of seven key electorates shows.

Of the seven coalition-held seats surveyed in ReachTEL polling commissioned by Fairfax Media, two are in NSW (Dobell and Lindsay), two are in Victoria (Corangamite and Deakin), and one each in South Australia (Mayo), Western Australia (Cowan), and Queensland (Bonner).

Only one looks like falling to Labor while another is on a knife-edge, the polling shows.

Labor would probably need to win all six marginal seats and have the Nick Xenophon-aligned candidate Rebekha Sharkie elected in Mayo to have a realistic chance of claiming the 21-seat haul needed for a one-seat majority, Fairfax reports.

A separate poll conducted for the Seven Network in the South Australian Liberal-held seat of Grey puts the Nick Xenophon Team (NXT) candidate easily ahead of sitting member Rowan Ramsey.

With the ReachTEL polling also showing a strong NXT vote in Mayo, that increases the chances of a hung parliament after the July 2 election.