New York - Wall Street stocks rose decisively in early trade on Thursday, with banking shares especially strong, as investors bet Britain will vote to stay in the European Union.
Although last-minute opinion polls have shown a tight contest, the strong gains in stocks suggested markets believe a "Remain" vote is virtually guaranteed.
But if the vote goes for Britain exiting the 28 member European Union, analysts say the result could be big losses in markets.
About 40 minutes into trade, the Dow Jones Industrial Average was at 17 923.86, up 0.8%.
The broad-based S&P 500 rose 0.8% to 2 101.72, while the tech-rich Nasdaq Composite Index gained 0.9% at 4 874.94.
Among large US banks, JPMorgan Chase, Bank of America and Citigroup all rose about 2.0% or more. London is the European headquarters for the banks and a vote for an EU pullout could force them to make costly changes to their operations.
The gains also came ahead of a release of the Federal Reserve's newest stress tests for banks, assessing their capital strength to withstand a crisis.
Macy's jumped 4.8% as it announced that president Jeff Gennette would become chief executive in the first quarter of 2017. Chief executive Terry Lundgren will shift to executive chairman.
Software company Red Hat fell 3.8% after projecting full-year earnings of $2.19 to $2.23 per share, compared to analyst forecasts for $2.24.