* Financials and healthcare firms top gainers

* NZ bourse marks best day in about two weeks

* NZ's Skycity Entertainment rises on profit jump

Sept 3 (Reuters) - Australian shares extended gains on Thursday, tracking a rally on Wall Street as stronger data from the world's top two economies and hopes of additional U.S. stimulus lifted investor sentiment.

The S&P/ASX 200 index rose as much as 0.9% and was up 0.6% at 6,101.2 by 1235 GMT, heading for a second straight session of gains.

Overnight, all three major U.S. stock indexes closed higher, boosted by a more than expected rise in U.S. factory orders and an expansion in U.S. private payrolls last month.

However, reports of a sluggish recovery in some sectors in the United States added to expectations for Washington to reach a deal on new stimulus to counter the blow from the COVID-19 pandemic.

Among gainers on the Australian benchmark index, blue-chip financial firms were the biggest boost, advancing 1.4% in their second straight session of gains.

Top lenders Commonwealth Bank of Australia rose 1.2%, while Westpac Banking Corp was up 1.9%.

Healthcare stocks added up to 1.7%, with heavyweights CSL Ltd and ASX-listed shares of Resmed Inc gaining 2.5% and 1.7%, respectively.

Among losers, gold stocks declined the most, down 1.6%, as bullion prices slumped more than 1.5% overnight on the dollar's rebound.

Newcrest Mining and Northern Star Resources lost 1.2% and 1.5%, respectively.

Across the Tasman Sea, New Zealand's benchmark S&P/NZX 50 index climbed as much as 1% to 12,020.6, in its best intraday percentage rise in about two weeks.

Fisher & Paykel Healthcare Corp and a2 Milk Co were among the top gainers, adding 1.9% and 2.7%, respectively.

Skycity Entertainment was the top gainer on the index, rising as much as 3.2% to its highest since July 30, after the casino operator posted a 46.3% rise in full-year net profit from continuing operations. (Reporting by Sameer Manekar in Bengaluru; Editing by Subhranshu Sahu)