US stock index futures were mixed on Tuesday as crude oil prices ticked up and markets awaited the midterm election results, Reuters reported.

Apple fell 4.5% in premarket trading after warning that the cost of memory chips would keep rising, pressuring its holiday-quarter gross margin. Palantir Technologies forecast fourth-quarter revenue above estimates after topping third-quarter expectations, but its shares fell 6.3%.

The Nasdaq-100 closed more than 10% below its all-time closing high on Monday, which Reuters said confirmed that the tech-heavy index had entered a correction. Investors have grown wary of Big Tech's AI spending and limited evidence of adequate returns. Several tech companies have also turned to the bond market to fund AI investments, raising concerns that debt-funded spending will be harder to justify as borrowing costs rise.

Chip stocks mostly rose, offsetting some tech losses. Nvidia gained 1.6% after four straight sessions of declines. AMD rose 2.8% ahead of its quarterly earnings, due after the bell.

Societe Generale analysts said in a note that concerns about government spending and deficits have contributed to market volatility. Morgan Stanley analysts said the elections should help remove a major market overhang and that the US market correction that began in June was in its "final innings." J.P. Morgan analysts said they view any dip caused by geopolitical tensions as a buying opportunity.

Crude oil prices rose after slumping in the previous session. An Iranian official said a deal to end the war was far off, and the United States struck Iran's Qeshm Island, according to the report. When asked on Monday whether he was considering striking Iran after the midterms, Trump said "no."