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Harris leads, Des Moines Register/Mediacom Iowa Poll shows

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Nvidia ( NVDA ) up on inclusion to the Dow Jones Industrial Average

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Marriott ( MAR ), Constellation Energy ( CEG ) fall after results

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Russell 2000 outperforms, benefiting from lower bond

yields

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Indexes down: Dow 0.95%, S&P 500 0.48%, Nasdaq 0.41%

(Updated at 11:55 a.m. ET/1555 GMT)

By Lisa Pauline Mattackal

Nov 4 (Reuters) - U.S. stock indexes slipped in choppy

trading on Monday, as investors braced for a pivotal week for

global markets in which Americans will elect a new president and

the Federal Reserve is likely to cut its benchmark policy rate.

Caution prevailed as the winner of the tightly contested

election between Democratic candidate Kamala Harris and

Republican Donald Trump might not be known for days after the

voting ends on Tuesday.

Some of the so-called "Trump trades" lost ground after a

recent poll showed Harris leading in Iowa, triggering a retreat

in dollar, bond yields and bitcoin.

Harris' odds have improved on several betting sites, an

election indicator that many market participants keep a close

watch.

Stocks turned lower despite a drop in the yield for the

benchmark U.S. 10-year Treasury, with volatile trading expected

in the run-up to the election outcome as investors await clarity

on the policy implications.

"It's a bit of calm before the storm this week ... the bond

market may be fading a little bit from the highs last week on

some of the new poll numbers coming out, suggesting a tighter

race," said Adam Turnquist, chief technical strategist for LPL

Financial.

"The playbooks of the 2016 and 2020 (elections) might be

thrown out the window... what dictates the level of volatility

will be when we get results."

CBOE's VIX measure of expected equity volatility is

trading at 22.54, well above its 30-day moving average of 19.45.

Stocks viewed as bets on a Trump win also jumped between

losses and gains. Trump Media & Technology Group ( DJT ) was

last up 1.4%.

Lower bond yields boosted rate-sensitive small-cap stocks,

with the Russell 2000 gaining 0.5%.

Investors, meanwhile, remained largely sure of a 25 basis

point interest-rate cut by the Fed in its November meeting,

whose decision is expected on Thursday.

The Dow Jones Industrial Average fell 397.83 points,

or 0.95%, to 41,654.14, the S&P 500 lost 27.52 points, or

0.48%, to 5,701.28 and the Nasdaq Composite lost 73.98

points, or 0.41%, to 18,165.94.

An index of energy stocks rose 1.4% as oil prices

rose after OPEC+ delayed plans to increase output.

Most megacap stocks lost ground, with Tesla

dropping 1.8% as the EV maker's China-made vehicle sales fell in

October.

However, chip heavyweight Nvidia ( NVDA ) rose 1.6%, after

S&P Dow Jones Indices said on Friday the company would replace

Intel ( INTC ) in the Dow Jones Industrial Average. Intel's ( INTC )

4.3% slide weighed on the Dow.

Hotel operator Marriott International ( MAR ) lost 2% after

cutting its 2024 profit forecast on weak domestic travel demand

in the U.S. and China.

Constellation Energy ( CEG ) was the biggest loser on the

S&P 500, slumping 11.1% after its results. Its losses dragged

the Utilities sector.

Advancing issues outnumbered decliners by a 1.64-to-1 ratio

on the NYSE and by a 1.1-to-1 ratio on the Nasdaq.

The S&P 500 posted 10 new 52-week highs and four new lows

while the Nasdaq Composite recorded 56 new highs and 100 new

lows.