US stocks stepped higher on Tuesday as Election Day got underway, with investors settling in to wait and see whether Kamala Harris or Donald Trump will shape the economy as the next president.

The tech-heavy Nasdaq Composite (^IXIC) led the gains, up 0.5%, while the benchmark S&P 500 (^GSPC) moved up roughly 0.3%. The Dow Jones Industrial Average (^DJI) opened just above the flatline on the heels of a losing day for stocks.

Americans are heading to the polls with Harris and Trump running neck-and-neck after a intensely contested presidential race. Investors are buckling in for market volatility, as the outcome may not become clear for days — or even weeks, if the result is disputed.

Read more: The Yahoo Finance guide to the presidential election and what it means for your wallet

Given the huge difference in the candidates' stances on the economy, a long wait for a declared winner could inject more uncertainty for markets. But historically, while the lack of a clear victory has brought turbulence in the short term, it has rarely halted the long-term trend for gains.

The dollar (DX-Y.NB) and Treasury yields traded broadly steady after retreating on Monday as as traders dialed back bets on a Trump win. The greenback nudged slightly lower, while the yield on the benchmark 10-year Treasury (^TNX) ticked about 1 basis point higher.

Dead ahead is the November policy decision from the Federal Reserve, which also has a lot at stake on Election Day. Chair Jerome Powell is overwhelmingly expected to bring in a 25 basis point rate cut at the end of the two-day meeting on Thursday.

Meanwhile, another big batch of quarterly earnings will roll in, with results from struggling AI server maker Super Micro Computer (SMCI) and Ferrari (RACE) on the docket.

The bitter seven-week strike at Boeing (BA) has ended after factory workers voted for a new contract offering a 38% pay hike. The planemaker's shares moved up roughly 2% in early trading.

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