By Will Horner

U.S. stocks opened mixed Wednesday ahead of a vote by lawmakers on impeaching President Trump during his final week in office.

The S&P 500 ticked up less than 0.1% after the opening bell, suggesting that the broad market index could have a choppy day. The Nasdaq Composite Index rose about 0.2%, while the Dow Jones Industrial Average retreated 2 points, less than 0.1%.

Stocks have drifted lower this week after notching record highs in early January as investors weighed the prospect of fresh government spending against political turmoil in Washington and still rising Covid-19 cases. Energy and banking are among the best performers so far in the new year as investors bet on companies that fared poorly in 2020 and are likely to benefit as the economy recovers.

"Markets are going to remain choppy for a while, but through it all, we remain cautiously optimistic," said Altaf Kassam, head of investment strategy for State Street Global Advisors in Europe. "The amount of fiscal stimulus that is possible will protect risky assets, and there is still a lot of cash on the sidelines."

U.S. inflation data out Wednesday showed that consumer prices increased only moderately last month, reflecting weak demand for a range of goods and services. Some economists expect inflation to pick up the pace as the economy grows faster later this year.

The Federal Reserve's beige book report, due at 2 p.m. ET, will offer the latest collection of business anecdotes across Fed districts, offering insights into how companies view the economy's prospects.

"We know the economy is going to be bigger at some point, so the market is willing to look forward," said Willem Sels, global chief investment officer at HSBC Private Banking. "We are still in a risk-on environment."

Ahead of the market open, General Motors rose over 4% after the auto maker said it was launching a new electric-truck business.

A selloff in U.S. government bonds eased late Tuesday following strong demand for an auction of new 10-year notes. On Wednesday, the yield on the 10-year Treasury note edged down to 1.126%, from 1.136% on Tuesday. Bond yields fall as the price rises.

Bond yields, which had advanced for seven consecutive days, are unlikely to climb much further, Mr. Kassam said.

"Rates are capped where they are now, and the Fed has effectively got a form of yield curve control in place because they have a commitment to buy bonds," he said. "I don't think we will see rates move much higher, because there is still a lot of demand."

House lawmakers plan to vote Wednesday on impeaching the president for the second time, just days before he is due to leave office. While the political rancor has weighed on market sentiment in recent days, most money managers are looking past the developments in Washington to focus on the prospects for additional fiscal stimulus.

"The market is largely focusing on the fundamentals around a Biden administration," said Mr. Sels.

Overseas, the Stoxx Europe 600 wavered between gains and losses.

Among major European equities, French retailer Carrefour jumped 15% after saying it was in talks with Canada's Alimentation Couche Tard over a potential merger.

In Asia, major indexes ended the day mixed. Japan's Nikkei 225 rose over 1%, and South Korea's Kospi gained 0.7%. The Shanghai Composite fell 0.3%, while Hong Kong's Hang Seng ticked down 0.2%.

Write to Will Horner at William.Horner@wsj.com

(END) Dow Jones Newswires

01-13-21 0947ET