Stocks remained mostly resilient in the face of another Trump controversy, this time over allegations that he divulged highly classified intelligence to Russian diplomats in the Oval Office.

While the market avoided a sharp swing downward, some investors worry Trump's difficulties could imperil his agenda.

"It is not just because they're necessarily thinking about anything as extreme as impeachment, but investors are worried that Congress won't be able to get anything done in this increasingly crazy environment in Washington," said Chris Low, chief economist of FTN Financial.

The Dow Jones Industrial Average ended down a hair at 20,979.68.

The broad-based S&P 500 slipped 0.1 percent to 2,400.67, while the Nasdaq Composite Index rose 0.3 percent to finish at a record for the second straight day at 6,169.87.

Nasdaq companies that gained more than one percent included Microsoft, eBay and Expedia.

Dow member Home Depot rose 0.6 percent after reporting an 11 percent increase in first-quarter profit to $2.0 billion.

But other leading retailers fell sharply following results, with T.J. Maxx parent TJX tumbling 4.0 percent and Dick's Sporting Goods slumping 13.7 percent.

Two other retailers that will report in the coming days, Wal-Mart Stores and Target, both lost about 1.5 percent.

Twitter rose 1.4 percent on news that co-founder Biz Stone will return to the social media company.