* Pfizer falls after profit misses expectations
* ISM data due at 10 a.m. ET
* Fed expected to stand pat on interest rates
* Indexes up: Dow 0.01 pct, S&P 0.01 pct, Nasdaq flat (Updates to open)
By Tanya Agrawal
Nov 1 (Reuters) - Wall Street was little changed at the open on Tuesday, a day after all three major indexes recorded their worst monthly performance since January.
Investors have been cautious about taking large positions due to uncertainty surrounding the U.S. presidential election and with the Federal Reserve poised to raise interest rates before the end of the year.
The market is also watching the outcome of the Fed meeting, which begins on Tuesday. While traders doubt the Fed will raise interest rates this week, they will be looking for signs to firm up their expectations for a hike at the central bank's meeting next month.
Chances of a rate hike in December were at around 78 percent, according to the CME Group's FedWatch Tool.
Wall Street ended barely changed on Monday as investors digested the latest large-scale corporate mergers as well as the most recent twist in a tumultuous U.S. presidential election.
Democrat Hillary Clinton held a 5 percentage point lead over Republican rival Donald Trump, according to a Reuters/Ipsos opinion poll released on Monday, down only slightly since the FBI said last week it was reviewing new emails in its investigation of Clinton ahead of the Nov. 8 election.
"The market is expected to be range bound until the election results next week," said Scott Brown, chief economist at Raymond James in St. Petersburg, Florida.
"The latest Clinton news has caused some uncertainty because the market had priced in her winning the election."
At 9:43 a.m. ET (1343 GMT) the Dow Jones industrial average was up 2.67 points, or 0.01 percent, at 18,145.09.
The S&P 500 was up 0.16 points, or 0.01 percent, at 2,126.31.
The Nasdaq Composite was up 0.21 points, or 0 percent, at 5,189.35.
Shares of Unitedhealth and Johnson & Johnson were down about 1 percent and weighed the most on the Dow.
Pfizer was down 0.9 percent at $31.44 after the drugmaker's quarterly profit fell below expectations.
Six of the 11 major S&P sectors were higher, with the energy index's 0.89 percent rise leading the gainers.
Oil edged up from one-month lows following its largest one-day slide in more than five weeks.
The S&P 500 index ended October with a 1.9 percent drop, the third straight month of decline. Still, the benchmark index is up about 4 percent for the year.
S&P 500 companies looked set to snap a long streak of quarterly earnings decline, with a number of companies reporting strong results. Profits are expected to have risen 3.1 percent, according to Thomson Reuters I/B/E/S.
L Brands fell 7.2 percent to $67 after a host of brokerages cut their price targets on the stock.
Archer Daniels Midland rose 5.9 percent to $46.13 after the agricultural products trader reported a far better-than-expected quarterly profit.
Economic data expected on Tuesday includes the Institute for Supply Management's index of national factory activity, which likely rose to 51.7 in October from 51.5 in the preceding month. The data is expected at 10 a.m. ET.
Advancing issues outnumbered decliners on the NYSE by 1,535 to 929. On the Nasdaq, 1,244 issues rose and 825 fell.
The S&P 500 index showed three new 52-week highs and four new lows, while the Nasdaq recorded 11 new highs and 22 new lows. (Reporting by Tanya Agrawal; Editing by Anil D'Silva)