U.S. stocks closed mostly lower on Monday as investors reassessed the prospects of key White House proposals, including tax reform, coming to fruition. "When you look at some of the areas that have helped the market, they are waning a bit here," said Daniel Deming, managing director at KKM Financial. "I think you're also seeing some valuation concerns as well. The Nasdaq composite closed 0.2 percent higher after briefly falling 1 percent. The Dow Jones industrial average ended about 45 points lower — after falling nearly 200 points earlier, with Goldman Sachs contributing the most losses. The 30-stock index also posted an eight-session losing streak, its longest since 2011. The S&P 500 dipped 0.1, with financials and telecommunications leading decliners. Financials were dragged by bank stocks, as the SPDR S&P Bank ETF (KBE) and the Regional Banking ETF (KRE) both fell around 0.5 percent. "This is coming as investors reassess how bad the news on health care actually is," said Kate Warne, investment strategist at Edward Jones. "There are definitely mixed views on that. This could be a catalyst for Republicans to do a better job with tax reform."

President Donald Trump Carlos Barria | Reuters

The Trump administration was dealt a body-blow Friday after a House bill aimed at replacing Obamacare was pulled from the floor. The GOP bill faced opposition not just from Democrats, but also from conservative and more moderate Republicans, and was not able to secure enough votes to pass. "It's been such a powerful rally that it's not surprising to see a pullback after a disappointment that big," said Maris Ogg, president at Tower Bridge Advisors, referring to the health care bill's defeat. "But the big picture really hasn't changed." The House vote was seen as crucial for the Trump agenda. Trump had said the repeal and replacement of Obamacare must happen before action can be taken on his other plans, including a major tax reduction. Stocks have rallied significantly since the U.S. election on hopes of lower taxes, deregulation and fiscal stimulus. "Certainly what happened on Friday makes it harder [to push tax reform], but we're not bogged down by it," said Jeremy Klein, chief market strategist at FBN Securities. "I think people are realizing we have a long way to go on tax reform." Trump said Friday the administration would move to try and slash taxes. The major indexes have taken a breather this month from their rip-roaring, postelection rally. The S&P and Dow were both down around 1 percent this month, while the Nasdaq held flat. "I don't think this is the beginning of a full-blown correction, but it's definitely a reversal in market sentiment," said Peter Cardillo, chief market economist at First Standard Financial.

U.S. Treasurys, which had fallen sharply immediately after the election, have also recovered ground this month after the Federal Reserve maintained its interest-rate outlook largely unchanged at its March meeting. "One by one, we're seeing the Trump trade unwind across all markets," said Adam Sarhan, CEO of 50 Park Investments, noting that assets like gold and the Mexican peso are around levels not seen since before the election. "A defensive stance is warranted until we see some bullish action take place, and a lot of that depends on what happens in D.C." The benchmark 10-year note yield fell to 2.37 percent, while the short-term two-year note yield dipped to 1.25 percent. The U.S. dollar declined to a four-month low against a basket of major currencies, with the euro near $1.087 and the yen around 110.6. Overseas markets also faced pressure following the American Health Care Act's defeat, with the pan-European Stoxx 600 index falling 0.4 percent. There are no major economic data due Monday, but this week investors will digest the third reading on fourth-quarter GDP and personal income data, among others.

Major U.S. Indexes